Status of Slender Mouse-Ear-Cress in Alberta 2009
Status of the Slender Mouse-ear-cress (Halimolobos virgata or Transberingia bursifolia subsp. virgata) in Alberta:
Update 2009
Alberta Wildlife Status Report No. 55 (Update 2009) Status of the Slender Mouse-ear-cress (Halimolobos virgata or Transberingia bursifolia subsp. virgata) in Alberta:
Update 2009
Prepared for: Alberta Sustainable Resource Development (ASRD) Alberta Conservation Association (ACA)
Update prepared by: Cheryl Bradley Much of the original work contained in the report was prepared by Ian Macdonald in 2005. This report has been reviewed, revised, and edited prior to publication. It is an ASRD/ACA working document that will be revised and updated periodically.
Alberta Wildlife Status Report No. 55 (Update 2009)
August 2009
Published By:
i Publication No. T/218 ISBN: 978-0-7785-8715-6 (Printed Edition) ISBN: 978-0-7785-8716-3 (On-line Edition) ISSN: 1206-4912 (Printed Edition) ISSN: 1499-4682 (On-line Edition)
Series Editors: Sue Peters, Robin Gutsell and Gavin Berg Illustrations: Brian Huffman Maps: Velma Hudson
For copies of this report, visit our web site at: KWWS VUGDOEHUWDFD¿VKZLOGOLIHVSHFLHVDWULVN DQGFOLFNRQ³'HWDLOHG6WDWXV´
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Contact: Information Centre - Publications $OEHUWD6XVWDLQDEOH5HVRXUFH'HYHORSPHQW Main Floor, Great West Life Building 9920 - 108 Street Edmonton, Alberta, Canada T5K 2M4
Telephone: (780) 944-0313 or 1-877-944-0313
This publication may be cited as:
$OEHUWD6XVWDLQDEOH5HVRXUFH'HYHORSPHQWDQG$OEHUWD&RQVHUYDWLRQ$VVRFLDWLRQ 6WDWXV of the Slender Mouse-ear-cress (Halimolobos virgata or Transberingia bursifolia subsp. virgata) LQ$OEHUWD 8SGDWH $OEHUWD6XVWDLQDEOH5HVRXUFH'HYHORSPHQW:LOGOLIH6WDWXV5HSRUW No. 55 (Update 2009). Edmonton, AB. 28 pp.
ii PREFACE
(YHU\¿YH\HDUVWKH)LVKDQG:LOGOLIH'LYLVLRQRI$OEHUWD6XVWDLQDEOH5HVRXUFH'HYHORSPHQW reviews the general status of wildlife species in Alberta. These overviews, which have been conducted in 1991 (The Status of Alberta Wildlife), 1996 (The Status of Alberta Wildlife), 2000 (The General Status of Alberta Wild Species 2000), and 2005 (The General Status of Alberta Wild Species 2005 DVVLJQLQGLYLGXDOVSHFLHV³UDQNV´WKDWUHÀHFWWKHSHUFHLYHGOHYHORIULVNWRSRSXODWLRQV that occur in the province. Such designations are determined from extensive consultations with professional and amateur biologists, and from a variety of readily available sources of population GDWD$NH\REMHFWLYHRIWKHVHUHYLHZVLVWRLGHQWLI\VSHFLHVWKDWPD\EHFRQVLGHUHGIRUPRUH detailed status determinations.
The Alberta Wildlife Status Report Series is an extension of the general status exercise, and provides comprehensive current summaries of the biological status of selected wildlife species in Alberta. Priority is given to species that are At Risk or May Be At Risk in the province, that are of uncertain status (Undetermined RUWKDWDUHFRQVLGHUHGWREHDWULVNDWDQDWLRQDOOHYHOE\WKH Committee on the Status of Endangered Wildlife in Canada (COSEWIC).
Reports in this series are published and distributed by the Alberta Conservation Association and WKH)LVKDQG:LOGOLIH'LYLVLRQRI$OEHUWD6XVWDLQDEOH5HVRXUFH'HYHORSPHQW7KH\DUHLQWHQGHG to provide detailed and up-to-date information that will be useful to resource professionals for managing populations of species and their habitats in the province. The reports are also designed to provide current information that will assist Alberta’s Endangered Species Conservation Committee in identifying species that may be formally designated as Endangered or Threatened under Alberta’s Wildlife Act. To achieve these goals, the reports have been authored and/or reviewed by individuals with unique local expertise in the biology and management of each species.
iii EXECUTIVE SUMMARY
Slender mouse-ear-cress (Halimolobos virgata or Transberingia bursifolia subsp. virgata) is an herbaceous plant distributed in the mixedgrass prairie on the plains of southeast Alberta and VRXWKZHVW 6DVNDWFKHZDQ DQG DFURVV VHPLDULG PRXQWDLQ UDQJHV DQG LQWHUYHQLQJ EDVLQV DQG plateaux of seven western states. It is listed as Threatened federally and also provincially by WKH6DVNDWFKHZDQJRYHUQPHQW,Q$OEHUWDHYDOXDWLRQRIDSURYLQFLDOVWDWXVUHSRUWUHVXOWHG in a recommended status of 'DWD'H¿FLHQW by the Alberta Endangered Species Conservation &RPPLWWHHDQGLWV6FLHQWL¿F6XEFRPPLWWHH5HVXOWVRIDGGLWLRQDOVXUYH\VLQNQRZQDQGSRWHQWLDO habitat for slender mouse-ear-cress are incorporated into this updated status report to assist in the evaluation of its provincial status.
Suitable habitat for slender mouse-ear-cress in Alberta is characterized as undulating to rolling QDWLYHJUDVVODQGRQVLOW\WRVDQG\GHSRVLWVRIÀXYLDORUHROLDQRULJLQ,WPD\EHDVVRFLDWHGZLWK ephemerally wet depressions and drainages. Fourteen subpopulations are recognized in Alberta: RQHLVUDQNHGDVH[WLUSDWHGRQHDVKLVWRULFDOWKUHHDVIDLOHGWR¿QGGXULQJVXEVHTXHQWVXUYH\VDQG nine as extant. Substantial rare plant search effort over the last few decades, and particularly within the last few years, in apparently suitable habitat has resulted in reports of only a few additional subpopulations of slender mouse-ear-cress. The extent of occurrence of all subpopulations in $OEHUWDLVDERXW NP2 WKDWRIRQO\H[WDQWRQHVLVDERXWNP2. Considering only extant VXESRSXODWLRQVWKHDUHDRFFXSLHGE\VOHQGHUPRXVHHDUFUHVVLVHVWLPDWHGWREHNP2 (the VXPRIRFFXSLHGNP[NPVTXDUHV 7KLVQXPEHUFRXOGEHOHVVWKDQNP2, based on the number and maximum size of unique locations in the Alberta Natural Heritage Information Centre database.
The provincial population of slender mouse-ear-cress is estimated to be in the order of several thousand (3000–7000) reproducing individuals in years when conditions are suitable for JHUPLQDWLRQDQGJURZWK'DWDRYHUPXOWLSOH\HDUVDWVRPHVLWHVLQGLFDWHODUJHÀXFWXDWLRQVLQ number of reproducing individuals, depending on environmental conditions such as timing and amount of rainfall in spring. Alberta’s extant population of slender mouse-ear-cress is DSSUR[LPDWHO\ NP IURP WKH FORVHVW NQRZQ VXESRSXODWLRQ LQ 6DVNDWFKHZDQ DQG NP IURPWKHQHDUHVWVXESRSXODWLRQLQWKH6ZHHWJUDVV+LOOVRI0RQWDQD7KHQH[WQHDUHVWNQRZQ SRSXODWLRQVDUHDERXWNPVRXWKLQWKH7HQGR\0RXQWDLQVRIVRXWKZHVW0RQWDQDDQGLQWKH $EVDURND5DQJHRIQRUWKZHVW:\RPLQJ
Loss of native grasslands within the range of slender mouse-ear-cress is affecting habitat quality and availability. Native prairie decline is caused primarily by agriculture expansion, urban development, oil and gas development and the construction of transportation and utility corridors, as well as the spread of invasive non-native species in fragmented landscapes. Since 1970, bare ground resulting from agriculture (cultivation) and industrial development has increased 40% and linear disturbance has increased 93% in a regional study area that encompasses all of the range of extant slender mouse-ear-cress subpopulations. The trend in loss of native grasslands is expected to continue. Other potential limiting factors for slender mouse-ear-cress are climate FKDQJHDQGDOWHUHG¿UHDQGJUD]LQJUHJLPHVEH\RQGWKHUDQJHRIQDWXUDOYDULDWLRQ
A draft recovery strategy for slender mouse-ear-cress in Canada has recently been developed by Environment Canada.
iv ACKNOWLEDGEMENTS
For the original 2005 report prepared by Ian Macdonald: Bonnie M. Smith (University of Calgary) for her generosity in sharing her experience with the VSHFLHVLQ$OEHUWDZLWKRXWZKLFKWKLVUHSRUWZRXOGQRWEHSRVVLEOH &DQGDFH(OFKXN &DQDGLDQ Wildlife Service [CWS]) for sharing information on her relocations in the province from 2004, and for her fresh insight into the habitats of the species; Susan Peters (Alberta Conservation $VVRFLDWLRQ>$&$@ IRUKHUHQFRXUDJHPHQWLQWKH¿HOGVXUYH\DQGUHVHDUFKSKDVHVRIWKLVSURMHFW DQGKHUH[FHOOHQWWKRURXJKDQGLQVLJKWIXOUHYLHZRIWKLVUHSRUW $QG\'LGLXN &:6 DQG5RELQ *XWVHOO $OEHUWD6XVWDLQDEOH5HVRXUFH'HYHORSPHQW>$65'@ IRUWKHLUVXSSRUWRIWKHDQG ¿HOGVXUYH\DQGUHVHDUFKSKDVHVRIWKLVUHSRUW 1\UHH6KDUS $&$ IRUKHUUHYLHZRIWKH¿QDO VWDJHVRIWKLVUHSRUW .VHQLMD9XMQRYLF $OEHUWD1DWXUDO+HULWDJH,QIRUPDWLRQ&HQWUH>$1+,&@ IRUSURYLGLQJLQIRUPDWLRQRQWKHNQRZQVLWHVLQ$OEHUWD -RKQ5LQWRXO $1+,& IRULQIRUPDWLRQRQ the reported Rosedale and Cypress Hills sites and conservation issues in Alberta; Sheila Lamont 6DVNDWFKHZDQ&RQVHUYDWLRQ'DWD&HQWUH>6&'&@ -HII.HLWK 6&'& DQG$QQ*HUU\ 6&'& IRULQIRUPDWLRQRQWKHUHFHQWHIIRUWVWRORFDWHWKHVSHFLHVLQ6DVNDWFKHZDQDQGFODUL¿FDWLRQRI WKH&\SUHVV+LOOVVLWHV 0LNH6KFKHSDQHN 7KH&DQDGLDQ0XVHXPRI1DWXUH IRUORFDWLQJ+- 6FRJJDQ¶VRULJLQDOGDWD¿OHUHFRUGRI0(0RRGLH¶V FROOHFWLRQIURPWKH5RVHGDOHORFDWLRQ DQGWR'U0DUFLD:DWHUZD\ 0F*LOO8QLYHUVLW\ 'U3DXO0&DWOLQJ $JULFXOWXUHDQG$JUL food Canada) and Christine Niezgoda (Vascular Plant Herbarium, Field Museum, Chicago, IL) IRUWKHLUVHDUFKHVIRUWKHDFWXDO5RVHGDOHVSHFLPHQ %RQQLH+HLGHO :\RPLQJ1DWXUDO'LYHUVLW\ 'DWD&HQWHU IRUVKDULQJKHULQIRUPDWLRQRQWKHVSHFLHV¶KDELWDWVDQGGLVWULEXWLRQLQ:\RPLQJDQG Montana, and for providing the invaluable correspondence with Walter Fertig (Grand Staircase- (VFDODQWH1DWLRQDO0RQXPHQW RQKLVNQRZOHGJHRIWKHORFDWLRQVDQGKDELWDWVIRUWKHVSHFLHV LQ:\RPLQJDQG0RQWDQD 'U&&&KLQQDSSD 8QLYHUVLW\RI&DOJDU\ IRUDOORZLQJDFFHVVWR WKHKHUEDULXPFROOHFWLRQV %RE+DOH 'XFKHVV&RPPXQLW\3DVWXUH$VVRFLDWLRQ DQG)UHG:LWWLJ (Landowner, Burstall, SK) for providing grazing management information on the locations under WKHLUPDQDJHPHQWLQ$OEHUWD -DQH/DQFDVWHU .HVWUHO&RQVXOWLQJ IRUVKDULQJKHULQIRUPDWLRQRQ the species in Alberta; Garry C. Trottier (CWS) for updated information on the species’ location LQ&DQDGLDQ)RUFHV%DVH6XI¿HOG1DWLRQDO:LOGOLIH$UHD 'U*HRIIUH\/+ROUR\G &:6 IRU LQIRUPDWLRQRQUHPDLQLQJQDWLYHSUDLULHLQZHVWHUQ&DQDGD DQG+XJK'-0F/HDQ $JULFXOWXUH and Agri-Food Canada) for information on prairie climate and drought conditions.
Preparation of this report was funded by the Alberta Conservation Association and the Fish and :LOGOLIH'LYLVLRQRI$OEHUWD6XVWDLQDEOH5HVRXUFH'HYHORSPHQW
For the 2009 update prepared by Cheryl Bradley: The assistance and contributions of several people in the preparation of this report is gratefully DFNQRZOHGJHG/RUQH)LWFKDVVLVWHGZLWK¿HOGZRUNLQ7RGG.HPSHU $OEHUWD1DWXUDO Heritage Information Centre) provided data on occurrences of slender mouse-ear-cress in Alberta DQGZRUNHGWRMRLQWO\UHVROYHLVVXHVDERXWWKHGH¿QLWLRQRIVXESRSXODWLRQV*DYLQ%HUJ $OEHUWD 6XVWDLQDEOH5HVRXUFH'HYHORSPHQW$65' DVVLVWHGLQDFTXLULQJEDFNJURXQGLQIRUPDWLRQ,DQ 0DFGRQDOG ERWDQLFDOFRQVXOWDQW SURYLGHGEDFNJURXQGLQIRUPDWLRQRQWKHVWDWXVUHSRUW that he wrote and reviewed collections of slender mouse-ear-cress in the University of Calgary KHUEDULXP%RQQLH6PLWK ERWDQLFDOFRQVXOWDQW SURYLGHGLQIRUPDWLRQRQSUHYLRXV¿HOGZRUNDQG collections. Ihsan Al-Shehbaz (Missouri Botanical Garden) provided label information for an
v historical collection near Rosedale and insights into revisions to the taxonomy of slender mouse-ear- FUHVV'DUF\+HQGHUVRQDQG&DQGDFH1HXIHOG &DQDGLDQ:LOGOLIH6HUYLFH&:6 VKDUHGLQIRUPDWLRQ RQRFFXUUHQFHVRIVOHQGHUPRXVHHDUFUHVVLQ6DVNDWFKHZDQNH\¿HOGLGHQWL¿FDWLRQFKDUDFWHUVDQG DSSURSULDWHVXUYH\WHFKQLTXHV%RQQLH+HLGHO :\RPLQJ1DWXUDO'LYHUVLW\'DWDEDVH 3HWHU/HVLFD (University of Montana) and Scott Mincemoyer (Montana Natural Heritage Program) helped with obtaining information on occurrences in Montana. Information on recent rare plant search effort in SRWHQWLDOKDELWDWIRUVOHQGHUPRXVHHDUFUHVVZDVVKDUHGE\IHOORZERWDQLVWV'DQD%XVK %XVK(FRORJ\ -DQH/DQFDVWHU .HVWUHO5HVHDUFK &ODUHDQG.DWK\7DQQDV 5DQJHODQG&RQVXOWDQWV DQG&OLII:DOOLV &RWWRQZRRG&RQVXOWDQWV DVZHOODVE\$OEHUW/HHV -DFTXHV:KLWIRUG$[\V/WG 9HOPD+XGVRQ $OEHUWD&RQVHUYDWLRQ$VVRFLDWLRQ$&$ KHOSHGZLWKSURGXFWLRQRIPDSV7KLVUHSRUWEHQH¿WHGIURP UHYLHZVE\%RQQLH6PLWK'DQD%XVK6XH3HWHUV $&$ *DYLQ%HUJDQG5RELQ*XWVHOO $65'
Preparation of this report was funded by the Alberta Conservation Association and the Fish and :LOGOLIH'LYLVLRQRI$OEHUWD6XVWDLQDEOH5HVRXUFH'HYHORSPHQW
vi TABLE OF CONTENTS
PREFACE ...... iii
EXECUTIVE SUMMARY...... iv
$&.12:/('*(0(176...... v
,1752'8&7,21 ...... 1
SPECIES TAXONOMY...... 1
HABITAT...... 2
1. Habitat Attributes...... 2
2. Habitat Trends...... 3
CONSERVATION BIOLOGY...... 5
',675,%87,21...... 6
1. Alberta...... 6
2. Other Areas ...... 12
3238/$7,216,=($1'75(1'6 ...... 12
1. Alberta...... 12
2. Other Areas ...... 15
LIMITING FACTORS...... 16
/RVVDQG'HJUDGDWLRQRI+DELWDW ...... 16
2. Anthropogenic Climate Change...... 16
3. Altered Fire Regime...... 17
4. Altered Grazing Regime ...... 17
67$786'(6,*1$7,216 ...... 18
1. Alberta...... 18
2. Other Areas ...... 18
RECENT MANAGEMENT IN ALBERTA...... 18
vii TABLE OF CONTENTS continued: SYNTHESIS...... 19
/,7(5$785(&,7('...... 21
$SSHQGL['H¿QLWLRQVRIVWDWXVUDQNVDQGOHJDOGHVLJQDWLRQV ...... 27
LIST OF FIGURES
Figure 1 Occurrence record locations for slender mouse-ear-cress in Alberta...... 7
)LJXUH'LVWULEXWLRQRIVOHQGHUPRXVHHDUFUHVVLQ1RUWK$PHULFD...... 13
LIST OF TABLES
Table 1 Summary of data on number of plants for occurrences/subpopulations of slender mouse-ear-cress in Alberta...... 8
viii INTRODUCTION The purpose of this report is to summarize current and historical data on slender mouse- Slender mouse-ear-cress (Halimolobos virgata ear-cress in Alberta, in order to re-assess the [Nutt.] O.E. Schulz; recently changed to status of this species and develop conservation Transberingia bursifolia subsp. virgata) is strategies. an annual, biennial or short-lived perennial herbaceous plant found in mixedgrass prairie SPECIES TAXONOMY on the plains of southwest Saskatchewan and southeast Alberta, and in the Sweetgrass Hills Slender mouse-ear-cress from the western of northern Montana. It is also distributed United States and Canada was originally named across the semi-arid mountain ranges and Sisymbrium virgatum Nutt ex Torrey & A. Gray intervening basins and plateaux of seven in 1838. In 1924, it was re-named Halimolobos western states, from eastern California and virgata (Nutt.) O.E. Schulz. Recently, the taxon central Colorado north to southwest Montana has been included in a new genus Transberingia, and northwest Wyoming. The other subspecies based on analysis of DNA sequences in related of Transberingia bursifolia in Canada occurs taxa (Price et al. 2001, Al-Shehbaz and O’Kane north of the Arctic Circle. Despite extensive 6OHQGHUPRXVHHDUFUHVVLVFODVVL¿HGE\ survey effort in Alberta, the known population some taxonomists as a species Transberingia of slender mouse-ear-cress is estimated to virgata (Nutt.) N.H. Holmgren (Holmgren be in the order of several thousand (3000– et al. 2005) and by others as a subspecies 7000) reproducing individuals in years when Transberingia bursifolia subsp. virgata (Nutt.) conditions are favourable. Loss of native R.A. Price, Al-Shehbaz & O’Kane (Price et al. grasslands within the range of slender mouse- 2001). ear-cress is reducing habitat quality and availability. The new genus Transberingia includes two other taxa: Halimolobos mollis (Hooker) Rollins from Slender mouse-ear-cress is considered May Alaska, Yukon, Nunavut, Northwest Territories, Be At Risk* according to the 2005 general and Greenland; and Arabidopsis bursifolia status review (Alberta Sustainable Resource (de Candolle) Botschantsev from the Russian Development [ASRD] 2007). Evaluation of )DU (DVW 7KHVH WZR WD[D DUH QRZ FODVVL¿HG the 2005 slender mouse-ear-cress status report as one species Transberingia bursifolia (de (ASRD 2005) resulted in a recommendation of Candolle) Al-Shehbaz & O’Kane and also as 'DWD 'H¿FLHQW in 2005 (Alberta Endangered one subspecies Transberingia bursifolia subsp. 6SHFLHV &RQVHUYDWLRQ &RPPLWWHH 6FLHQWL¿F bursifolia (Al-Shehbaz and O’Kane 2003, Price Subcommittee 2005). In Saskatchewan, slender et al. 2001). mouse-ear-cress is listed as Threatened under that province’s :LOGOLIH $FW (Government of The key distinguishing feature that separates Saskatchewan 2008). Based on an assessment slender mouse-ear-cress from closely related by the Committee on the Status of Endangered taxa is the presence of multi-branched Wildlife in Canada (COSEWIC) in 2000, subappressed hairs (trichomes) sometimes slender mouse-ear-cress is listed as Threatened mixed with simple hairs on the upper parts of in Canada, and is on Schedule 1 of the WKHVWHPDQGFHQWUDOD[LVRIWKHLQÀRUHVFHQFH federal 6SHFLHVDW5LVN$FW (COSEWIC 2000, (rachis), instead of only sparse simple hairs or Government of Canada 2008). none at all.
6HH $SSHQGL[ IRU GH¿QLWLRQV RI VHOHFWHG VWDWXV The genus Halimolobos KDV EHHQ UHGH¿QHG designations. based on DNA sequencing to include eight
1 species in the southwestern United States and Alberta. Growing degree days is a cumulative northern and central Mexico, all characterized measure of the temperature above 5°C that by having fruits with large hairs mixed with indicates energy available for plant growth. smaller ones (Bailey et al. 2007). Slender Average annual precipitation is 333 mm; of mouse-ear-cress and other species in the genus that, 241 mm falls during the growing season. Transberingia are described as having no hairs The summer moisture index (degree days on the fruits, although some recent collections divided by mean precipitation) averages 7.0, of slender mouse-ear-cress from Saskatchewan the highest (and hence, driest) of any natural are reported to have fruits with hairs (C. Neufeld subregion in Alberta. A summer moisture pers. comm.). More taxonomic investigation LQGH[KLJKHUWKDQLQGLFDWHVWKDWVLJQL¿FDQW of the prairie population of slender mouse- PRLVWXUHGH¿FLWVDUHOLNHO\IRUH[WHQGHGSHULRGV ear-cress is suggested to ascertain the degree during the growing season (Natural Regions to which the population presents distinctive Committee 2006). High summer temperatures, features when compared to populations of the low summer precipitation, drying winds, and same or closely related taxa several hundreds of intense sunshine contribute to the high moisture kilometres to the southwest and to the north. GH¿FLWVLQPLGVXPPHU/RZZLQWHUVQRZIDOOV contribute little to soil moisture reserves. Halimolobos virgata continues to be a widely DFFHSWHG VFLHQWL¿F QDPH E\ 1RUWK $PHULFDQ In Alberta, slender mouse-ear-cress grows on agencies, other organizations and taxonomic VLOW\ WR VDQG\ SDUHQW PDWHULDO RI JODFLRÀXYLDO specialists at the time of writing this report GHSRVLWHG E\ JODFLDO PHOWZDWHU ÀXYLDO (Integrated Taxonomic Information System (deposited by rivers/streams) or eolian 2009). Authors of a key for the Mustard (deposited by wind) origin on undulating to family (Brassicaceae) being drafted for The rolling sandy plain and river valley slopes and )ORUD RI 1RUWK $PHULFD consider the taxon terraces (Bradley 2008). It may occur on sandy as Transberingia bursifolia ssp. virgata (Al- ÀXYLDOYHQHHURYHUPRGHUDWHO\FDOFDUHRXVWLOO Shehbaz in prep.). It is reported near, but not in, choppy sand hills or dunes. Elevation varies from 600 m to HABITAT 750 m. Habitat is generally described as dry to mesic. 1. Habitat Attributes - In Alberta, slender mouse-ear-cress is found in the Dry Mixedgrass Slender mouse-ear-cress grows mainly on soils Natural Subregion of the Grassland Natural WKDWDUHFODVVL¿HGDVRUWKLFEURZQFKHUQR]HPV Region (Alberta Natural Heritage Information and are of coarse texture (sandy loams or sands) Centre [ANHIC] 2005), in the lower South in sandy ecological/range sites (Adams et al. Saskatchewan River and Red Deer River basins. 2005). Soil map units in which slender mouse- The climate is continental, characterized by ear-cress has been reported include Bingville- extremes in temperatures with warm summers Cavendish (BVCV), Cavendish (CVD), and cold winters. In the Dry Mixedgrass Vendisant-Cavendish (VSCV), Foremost- Natural Subregion the mean annual temperature Purple Springs (FMPL) and Pemukan (PUN), is 4.2°C, the mean July temperature is 18.5°C, DOO FKDUDFWHUL]HG DV FRDUVHWH[WXUHG ÀXYLDO and the mean January temperature is -12.1°C RU ÀXYLDO YHQHHU RYHU WLOO .MHDUVJDDUG DQG (Natural Regions Committee 2006). There is an Pettapiece 1986). One location is in an area average of 113 frost-free days per year, and the of intersection of a sandy Cavendish-Purple average number of growing degree days during Springs (CVPL) map unit with a Foremost the growing season, April through August, (FMT) map unit characterized as medium- is 1318, the highest of any natural region in textured, moderately calcareous till. One
2 location is in a Rough Broken (RB1) map unit ((OHDJQXV FRPPXWDWD). The non-native that is undifferentiated parent material of river invasives, Kentucky bluegrass (Poa pratensis) valleys. and crested wheatgrass ($JURS\URQFULVWDWXP), have been reported at a few sites where slender It is suggested that slender mouse-ear-cress mouse-ear-cress is found (Environment Canada may be associated with ephemerally wet 2009). Historically, slender mouse-ear-cress depressions and drainages that experience a was reported from “meadows” in the Cypress slight alkalization of soils (Environment Canada Hills in Saskatchewan and Wood Mountain; 2009, Smith 1992, C. Bradley pers. obs.). It is however, these occurrences have not been also suggested that at some sites slender mouse- relocated (ASRD 2005, Environment Canada ear-cress preferentially occurs in the shelter 2009). of shrubs and cacti, perhaps relying on extra spring moisture from trapped snow (D. Bush In the United States, sites where slender pers. comm.). Small-scale habitat associations mouse-ear-cress has been reported range from for slender mouse-ear-cress are not well valley bottoms to ridge tops, from 1000 m to documented and require further investigation. 3600 m in elevation (Al-Shehbaz in prep.). In the Sweetgrass Hills of north-central Montana, Slender mouse-ear-cress usually occurs in native slender mouse-ear cress was found at 1402 m mixed grassland dominated by needle-and- in grassland dominated by needle-and-thread thread grass (6WLSDFRPDWD). Bare soil without grass, western wheatgrass and Idaho fescue vegetation is seldom more than 10 percent of ()HVWXFDLGDKRHQVLV) on thin soils over glacial the area of the ecological community. Co- gravels (collection of June 13, 1989 by E.C. dominant grasses may include blue grama grass 'DUÀHU*UD\+HUEDULXP %+HLGHO (%RXWHORXDJUDFLOLV), Sandberg’s bluegrass (Poa pers. comm., S. Mincemoyer pers. comm., Gray sandbergii), June grass (.RHOHULDPDFUDQWKD), Herbarium 2009). In the Tendoy Mountains northern wheatgrass ((O\PXV ODQFHRODWXV) or of southwest Montana, slender mouse-ear- western wheatgrass (3DVFRS\UXPVPLWKLL). Low cress occurs in open shrublands dominated sedge (Carex stenophylla) may also have more by big sagebrush and mountain mahogany on than 10 percent cover. Habitat may include valley terraces at 1700 m to 2300 m (Montana scattered clumps of sagebrush ($UWHPHVLDFDQD) Field Guide 2008, University of Montana and prickly pear cactus (2SXQWLDSRO\FDQWKD). Herbarium 2008, P. Lesica pers. comm.). In Wyoming, it is reported mostly in montane In southwestern Saskatchewan, slender mouse- habitats, especially sagebrush communities in ear-cress is found in mixed grassland habitats the vicinity of calcareous rock outcrops (ASRD similar to those in Alberta (Environment 2005). In northeast Utah, slender mouse- Canada 2009). In addition to occurring on ear-cress is associated with moist loamy to chernozemic soils of sandy to loamy texture gravelly substrates at 2100 m to 2700 m. At RQ ÀXYLDO RU HROLDQ GHSRVLWV LW LV UHSRUWHG WR the southwest limit of its range in east-central inhabit sites with regosolic soils and lacustrine California, slender mouse-ear-cress occurs deposits. It is most commonly found in LQ ³PHDGRZV´ DQG VHHSV LQ SLQ\RQMXQLSHU native grassland communities dominated ZRRGODQGDWPWRP &DOÀRUD by June grass, needle-and-thread grass and California Native Plant Society 2008). wheat grasses, often with some sagebrush or prickly pear cactus. Slender mouse-ear- 2. Habitat Trends - Grasslands are one of cress is reported to be occasionally associated North America’s most threatened ecosystems with wild rose (Rosa woodsii), snowberry (Gauthier et al. 2003). Mixedgrass and (6\PSKRULFDUSRVRFFLGHQWDOLV and silverberry shortgrass prairie have been reduced to
3 20%–30% of their former extent, the decline footprint of more than 1.9 km/km2 to be “highly caused primarily by agriculture expansion, developed.” urban development, oil and gas development and the construction of transportation and $ PRGL¿HG SODQW FRPPXQLW\ LV DVVRFLDWHG utility corridors. In Alberta, native prairie with anthropogenic disturbances in mixedgrass is estimated to have declined by 60%–70% prairie, not only in areas where vegetation since colonization in the late 1890s (Alberta and soil have been directly impacted by the Environmental Protection 1997, Alberta land use but also indirectly through invasion Prairie Conservation Forum 2000). The Dry RI QRQQDWLYH VSHFLHV LQWR DGMDFHQW DUHDV RI Mixedgrass Natural Subregion has a higher native vegetation (AXYS 2005, Bradley 2003, proportion of intact grasslands remaining Great Sand Hills Advisory Committee 2007, (about 55%) than other subregions of the Henderson 2007, Rowland 2008, Smith 2007, Grassland Natural Region; however, the extent Smith and Taylor 2007, Smith and Tulis 2007). to which these are in native condition is not Invasive, non-native species commonly found well documented. in grasslands in southern Alberta include crested wheatgrass ($JURS\URQ FULVWDWXP), Kentucky Native prairie continues to decline because of bluegrass (Poa pratensis), smooth brome human activities and the spread of invasive non- (Bromus inermis), downy brome (Bromus native species in fragmented landscapes. The WHFWRUXP) and leafy spurge (Euphorbia esula). energy sector footprint has been increasing at a Once established, these invasive species rate of about 9000 hectares per year across the persist. Grassland Natural Region (Prairie Conservation Forum 2008). A cumulative effects assessment Crested wheatgrass establishes in habitats of a regional study area extending from suitable to slender mouse-ear-cress (Bradley Medicine Hat to the Red Deer River and from 2008). It is reported to spread by seed into native the west boundary of the Canadian Forces Base grasslands at rates up to 0.8 m/year (Henderson &)% 6XI¿HOGWR+LJKZD\HVWLPDWHVEDUH 2007, Henderson and Naeth 2005). Crested ground resulting from agriculture (cultivation) wheatgrass is associated with decreased plant and industrial development has increased from community diversity, decreased soil organic 10.2 ha/km2 in 1970 to 14.3 ha/km2 in 2005, an matter and reduced carbon sequestration increase of 40% (Environment Canada 2008a). (Christian and Wilson 1999, Heidinga and Linear disturbance has increased from 2.7 km/ Wilson 2002, Henderson and Naeth 2005, km2 to 5.2 km/km2, an increase of 93%, over Jordan et al. 2008). WKHVDPHWKLUW\¿YH\HDUSHULRG7KLVWUHQGLV expected to continue. Leafy spurge also establishes in habitats suitable to slender mouse-ear-cress (Bradley 2008). It 6HYHUDO PDMRU SLSHOLQHV DQG JDV ¿HOGV KDYH is reported to spread by seed and roots into been developed over the last decade in native native grasslands at rates of up to one metre grasslands within the known provincial range of per year (National Park Service 2003). Leafy slender mouse-ear-cress and more development spurge outcompetes native species by shading, LV SURSRVHG *DV ¿HOG GHYHORSPHQW ZLWK usurping available water and nutrients, and densities up to 16 wells per section (6 wells through plant toxins that prevent the growth per km2) has resulted in total disturbed area of other plants underneath it (National Park of up to 12% and linear disturbance footprint Service 2003). of up to 12 km/km2 (Smith and Tulis 2007). The Great Sand Hills Advisory Committee One location where slender mouse-ear-cress (2007) considers anthropogenic disturbance was reported in 1884 (Medicine Hat [EO
4 008]) is no longer suitable habitat as a result (U\VLPXPLQFRQVSLFXXP, is that the upper stem of anthropogenic disturbance for municipal generally has longer straight, simple or forked development and establishment of crested wheat hairs (trichomes) mixed with shorter, freely grass. At a location where slender-mouse-ear- branching hairs. Leaves of the basal rosette are cress was reported in 1978 (Sandy Point, north of up to 6 cm long and 15 mm wide, tapered to McNeill [subEO 002]), surveyors undertaking the stalk and wavy-toothed. Stem leaves are VXEVHTXHQW VHDUFKHV QRWHG D PRGL¿HG SODQW smaller, the upper leaves stalkless and clasping community dominated by crested wheatgrass with small basal lobes (auricles). Numerous (ASRD 2004, Macdonald 2002). Two other VPDOOÀRZHUVDERXWPP±PPDFURVVRFFXU locations where slender mouse-ear-cress has on stalks clustered at the tip of the stem. Each not been found during surveys within the last ÀRZHU KDV IRXU ZKLWH SHWDOV DQG IRXU KDLU\ 10 years (west of McNeill [EO 005]; north VHSDOV7KHÀRZHULQJVWHP DUDFHPH HORQJDWHV of Duchess [EO 009]) have experienced in fruit such that the linear pods (siliques) are HVWDEOLVKPHQW RI PRGL¿HG SODQW FRPPXQLWLHV erect and borne on stalks 7 mm–11 mm long as a result of development of a pipeline that usually extend at a 45 degree angle from corridor, gas wells and access roads (Bradley the stem. Pods are 2 cm–4 cm long and 1 mm 2008). Leafy spurge invasion has been noted at wide, generally hairless and cylindrical. Seeds one location of slender mouse-ear-cress (south are crowded in two irregular rows in each of of Empress [EO 017]). Long-term impact of two locules. invasive, non-native species on slender mouse- ear-cress presence is not known (Environment Other mustards of similar appearance occurring Canada 2009). in habitat similar to slender mouse-ear-cress FDQEHGLVWLQJXLVKHGLQIUXLWE\KDYLQJÀDWWHQHG A conclusion from the information provided in pods (Arabis holboellii var.UHWURIUDFWD$UDELV this section is that a large portion of potential GLYDULFDUSD $UDELV KLUVXWD) or four-angled native upland and river valley habitat for slender pods with a beak and seeds in one row in each mouse-ear-cress has been lost owing to human locule (Erysimum spp.). Stems of Erysimum activity over the last century. Substantial further spp. have only simple or forked (malpighian) loss is predicted if current trends in land use hairs, often dense, and lack the scattered, and non-native plant species invasion continue shorter freely-branching hairs characteristic of without measures being taken to identify and slender mouse-ear-cress. protect sites where slender mouse-ear-cress occurs. In Alberta, slender mouse-ear cress has been UHSRUWHG EHDULQJ ÀRZHUV DQG LPPDWXUH IUXLW CONSERVATION BIOLOGY during mid-May to late June and bearing mature fruit and dispersing seed during late Slender mouse-ear-cress is a biennial or June to mid-July (ASRD 2005, ANHIC 2008, sometimes short-lived perennial or annual herb B. Smith pers. comm.). Each stem bears up to in the mustard family (Brassicaceae) (Kershaw WZRGR]HQÀRZHUVDQGHDFKOLQHDUSRGFRQWDLQV et al. 2001, Moss 1983). The plant is tap- a few dozen seeds; therefore, individual plants rooted and rosette-forming with one to several on average likely produce between 100 and erect, simple or branched stems 10 cm–40 cm 400 seeds (ASRD 2005). Further study would tall. Plants vary greatly in stature, from tall, be required to determine whether pollination branched and robust to short, single-stemmed in slender mouse-ear-cress is wind- or insect- and thin. A feature that distinguishes slender mediated, and whether self-fertilization occurs. mouse-ear-cress from mustards of similar Seeds are small (<1 mm) and wingless, with a appearance, including Arabis hirsuta and seed coat that is minutely reticulate. The pods
5 split open at maturity while still attached to shelter it from grazing and trampling (D. Bush the plant, readily dispersing the seeds, most of pers. comm.). Slender mouse-ear-cress is not which likely fall near the parent plant, although obviously a disturbance-dependent species, some may be carried farther by wind, water although small disturbances, such as the action or animals. Leaves rapidly dry up, stems of hoofs exposing bare soil or creating moist turn brittle and do not appear to persist long depressions may provide suitable microhabitats after seed dispersal (C. Bradley pers. obs., C. IRU LWV HVWDEOLVKPHQW 3HULRGLF ¿UH PD\ DOVR Neufeld pers. comm.). EHQH¿W VOHQGHU PRXVHHDUFUHVV E\ UHOHDVLQJ nutrients and removing competition of grasses There is no information on seed longevity, the and shrubs. rates of seed germination, or survival rates of VHHGOLQJVIRUVOHQGHUPRXVHHDUFUHVV7KH¿UVW DISTRIBUTION year following seed germination, a tap root and URVHWWHRIOHDYHVPD\JURZ$ÀRZHULQJVWHPLV 1. Alberta – All reports of slender mouse-ear- generally produced in one or more subsequent cress in Alberta are within the Dry Mixedgrass years. Little information is available on how Natural Subregion of the Grassland Natural long individual plants live. For many years 5HJLRQDQGPRUHVSHFL¿FDOO\LQWKHZDWHUVKHGV slender mouse-ear-cress was described as of the Red Deer River below Drumheller and biennial, occasionally annual (Moss 1983); the South Saskatchewan River below Medicine however, more recent taxonomic treatments Hat (Figure 1). Occurrences are concentrated consider it a perennial, perhaps short-lived in the Bindloss Plain Ecodistrict (Adams et (Price et al. 2001). al. 2005). This Ecodistrict is characterized as KDYLQJ VXU¿FLDO PDWHULDOV SUHGRPLQDQWO\ RI There is evidence that the number of plants at JODFLRÀXYLDODQGHROLDQRULJLQDQGWKHKLJKHVW RQH ORFDWLRQ PD\ ÀXFWXDWH VXEVWDQWLDOO\ IURP annual moisture index (ratio of total annual year to year, suggesting that local weather degree days to total annual precipitation) in the FRQGLWLRQV LQÀXHQFH VHHG SURGXFWLRQ VHHG Dry Mixedgrass Natural Subregion. germination and plant growth. Slender mouse- ear-cress may be associated with habitats that Fourteen occurrences or subpopulations make are wet in the spring (Environment Canada up the known population of slender mouse- 2009). Lower than average precipitation in ear-cress in Alberta, as of January 2009. These a given year may suppress germination and element occurrences are listed in Table 1 and growth, resulting in underestimation of size mapped in Figure 1. Where information on and extent of a population. Therefore, surveys genetics and propagule dispersal is lacking, are best planned for years when there is above HOHPHQW RFFXUUHQFHV DUH GH¿QHG DV VHSDUDWH average precipitation during April, May and populations no less than 1 km apart if June. intervening habitat conditions are unsuitable, and no more than 3 km apart if intervening Slender mouse-ear-cress appears to be tolerant habitat conditions are suitable for the species of light to moderate livestock grazing pressure. (NatureServe 2004). Of the fourteen slender It does not appear to be preferentially selected mouse-ear-cress occurrences in Alberta, one E\JUD]HUVDQGPD\EHDYRLGHG,WLVFODVVL¿HG is considered extirpated, one is considered as tolerant of heavy grazing pressure in KLVWRULFDO WKUHH DUH FRQVLGHUHG IDLOHGWR¿QG range surveys in Wyoming (ASRD 2005). In and nine are considered extant (ANHIC 2008, locations with heavy livestock use, slender Hammerson et al. 2008). mouse-ear-cress is generally found close to shrubs and cacti, suggesting these plants
6 Figure 1: Occurrence record locations for slender mouse-ear-cress in Alberta. See Table 1 for information on each record. Occurrence numbers are assigned by the Alberta Natural Heritage Information Centre.
7KH¿UVWFROOHFWLRQRIVOHQGHUPRXVHHDUFUHVV second collection by John Macoun, generally in Alberta was made in 1894 by John Macoun described as from the Cypress Hills, has been near the police barracks at Medicine Hat, determined to be likely from Saskatchewan and known as Police Point (EO 008 in Table 1). The not Alberta (ASRD 2005). FROOHFWLRQLV¿OHGZLWKWKH&DQDGLDQ0XVHXPRI Nature National Herbarium. This occurrence The second collection of slender mouse-ear- is considered extirpated because substantial cress was made in 1914 by M.E. Moodie in habitat alteration has occurred as a result of “the vicinity of Rosedale in prairies north of the municipal development, and slender mouse- Red Deer Valley at 2200-2500 ft on damp soil ear-cress has not been found during subsequent near sloughs” (EO 033 in Table 1) (Al-Shehbaz rare plant surveys in and near Medicine Hat. A pers. comm.). The collection, only recently
7 Table 1: Summary of data on number of plants for occurrences/subpopulations of slender mouse-ear-cress in Alberta. Data are from the Alberta Natural Heritage Information Centre (ANHIC) database of rare plant occurrences; element occurrence (EO) numbers and ranks are assigned by ANHIC. See Figure 1 for occurrence locations. EO Rank: H = historical; F = failed-to-find; E = extant; X = extirpated. N/a indicates that data are not available.
Site Name EO# EO Max. Survey Date(s) Population Area (sub) Rank Recorded Estimate1 (m2) Pop. (Year) Rosedale 033 H >1 (1915) 1915-06-05 >1 n/a
Duchess Pasture; 009 F 49 (1997) 1997-06-02 54 25 Matzhiwin Creek 2002-xx-xx 0 0 2005-05-20 0 0 2008-06-16 0 0
W of Remount Pasture; 015 E 47 (2008) 2008-07-02 47 300 N Boundary CFB Suffield
Cavendish; 018 E 87 (2008) 2008-07-05 87 600 Remount Pasture NW
Remount Pasture S; 007 E 398 (2004) 1997-05-31 0 0 N Boundary CFB Suffield 2002-xx-xx 0 0 2004-06-07 398 1200 2008-07-02 25 400
Remount Pasture SE; 003 E 919 (2004) 1997-05-30 15 900 1997-05-30 1 <1 1997-05-30 200 1500 2002-xx-xx 0 0 2004-06-26 919 1000
Bindloss SW; 029 E 96 (2007) 2007-05-29 96 n/a Remount Pasture NE 2008-06-06 15 160
Bindloss W; 030 E 130 (2007) 2007-05-27 130 n/a Minor Ranch 2008-06-13 1 <1
Empress S; 016 E 7 (2008) 2008-07-03 7 10 Big Loop S. Sk. R.
Empress; 017 E 15 (2008) 2008-07-03 15 10 Big Loop S. Sk. R.
Linstead Flats; 001 F 20 (1995) 1995-06-23 20 375 CFB Suffield National Wildlife 2004-xx-xx 0 0 Area 2005-06-26 0 0
S Sk. R. pipeline crossing; 005 F >100 (1997) 1997-05-29 >100 200 W of McNeill 2002-xx-xx 0 0 2004-xx-xx 0 0
8 Table 1 continued.
Site Name EO# EO Max. Survey Date(s) Population Area (sub) Rank Recorded Estimate1 (m2) Pop. (Year) McNeill N 0102 E 251(2007) 1997-05-24 56 200 1997-05-24 16 20 1997-05-24 33 30 1999-07-12 12 200 2002-xx-xx 0 0 2004-06-06 145 100 2004-06-24 39 10 2004-09-14 14 n/a 2007-07-01 8 n/a 2007-07-02 21 n/a 2007-07-02 2 n/a 2007-07-02 150 250 2007-07-02 21 n/a 2007-07-27 36 1114 2007-07-27 2 n/a 2007-07-27 2 10 2007-07-27 7 3 2007-07-27 1 <1 2007-07-27 1 <1 2008-06-15 17 400 2008-06-15 13 n/a 2008-07-01 13 n/a 2008-07-02 29 16
(McNeill N, Sandy Point; (002)2 (F) >1(1978) 1978-05-16 >1 n/a Hwy 41 at S. Sk. R.) 1991-06-07 0 0 1997-05-24 0 0 2002-xx-xx 0 0 2003-xx-xx 0 0
Police Point; 008 X >1 (1884) 1884-05-31 >1 n/a Medicine Hat 1991-06-07 0 0 2002-xx-xx 0 0
1 Population estimate is the number of individuals counted in a cluster or several clusters, as reported to ANHIC. Multiple (sub)population estimates on the same date apply to different plant clusters within the same subpopulation.
2 Sub EO 002 has recently been included in EO 010 and is not shown on the map in Figure 1. For three decades it was considered a separate EO, and is the only known site within the subpopulation located west of the river.
UHORFDWHGLV¿OHGZLWKWKH0LVVRXUL%RWDQLFDO Six decades elapsed before slender mouse- *DUGHQ 0RRGLH 7KLV RFFXUUHQFH LV ear-cress was collected again, in 1978 by John considered historical, since slender mouse-ear- Hudson at Sandy Point north and east of the cress has not been reported from the vicinity Highway 41 Bridge in the South Saskatchewan in several decades (ANHIC 2008); however, River valley (EO 010, subEO 002; Table 1). A targeted search in the vicinity has yet to be FROOHFWLRQ LV¿OHGDWWKH$JULFXOWXUH conducted. Canada Herbarium in Ottawa. In four separate searches since 1991, surveyors have failed to
9 ¿QG VOHQGHU PRXVHHDUFUHVV RQ WKH WHUUDFHV UHFRUGHGDV³LQYDOLGLGHQWL¿FDWLRQ´LQ 7 where the collection was made, noting Kemper pers. comm.), and are therefore not considerable invasion by crested wheatgrass included in Table 1 or Figure 1. Four Alberta (ASRD 2004, Macdonald 2002, Smith 1992 collections of slender mouse-ear-cress from and 2000). This location is now considered ORFDWLRQVLGHQWL¿HGLQWKH VXUYH\DUH¿OHG part of a larger element occurrence extending at the University of Calgary herbarium: Duchess to the east and south (EO 010). Pasture EO 009 (UAC 56451) Remount Pasture 003 EO (UAC 56455) and near McNeill EO In 1995, slender mouse-ear-cress was collected 010 (UAC 56454 , UAC 56457). in upland sand plain habitat during an inventory of vascular plants in the Canadian Forces Base Several subsequent intense and targeted 6XI¿HOG1DWLRQDO:LOGOLIH$UHD (2 7DEOH searches between 1997 and 2008 resulted in 0DFGRQDOG &ROOHFWLRQV DUH ¿OHG FRQ¿UPDWLRQRIWKHSUHVHQFHRIVOHQGHUPRXVH with the University of Calgary herbarium and ear-cress at three locations, two in the Remount the Provincial Museum in Edmonton (B95.9.6). Pasture and one near McNeill (EO 003, EO 6XUYH\RUVIDLOHGWR¿QGSODQWVGXULQJVHDUFKHV DQG(2 DQGIDLOXUHWR¿QGLWDWIRXU at this location, near Linstead Flats, in 2004 and locations (EO 005, EO 009, EO 006 and EO 2005 (Elchuk 2005); hence, this occurrence is 032; the latter two were subsequently found FRQVLGHUHGIDLOHGWR¿QG to be invalid, as described above). Additional VXUYH\VDUHQHHGHGWRGHWHUPLQHZLWKFRQ¿GHQFH In 1997, seven new upland occurrences of if slender mouse-ear-cress is extirpated at the slender mouse-ear-cress (EO 003, EO 005, two occurrences where surveyors have failed to EO 006, EO 007, EO 009, EO 010 and EO ¿QGSUHYLRXVO\UHSRUWHGSRSXODWLRQVLQRYHUD 032; see Table 1) were reported during a rare decade—the Duchess Pasture near Matzhiwin plant survey along a proposed pipeline route Creek (EO 009) and the pipeline corridor between the Alberta/Saskatchewan border near crossing of the South Saskatchewan River (EO McNeill and westward to beyond Matzhiwin 005). Alteration of native plant communities Creek near Duchess (Smith 2000). Locations EHFDXVHRIPDMRUSLSHOLQHFRUULGRUFRQVWUXFWLRQ ZHUHLGHQWL¿HGDVGLVWDQFHVDORQJWKHSLSHOLQH DQGJDV¿HOGGHYHORSPHQWPD\EHFRQWULEXWLQJ and legal land descriptions (section/township/ to the plant’s absence. range), and not by more precise GPS coordinates (B. Smith pers. comm.). Population size In 2007, during rare plant survey along a included counts of plants of the current year proposed pipeline route from Hardisty south DQG DOVR FRXQWV RI SODQWV LGHQWL¿HG DV ³ROG through McNeill and eastward, slender mouse- stems” from the previous year. Three Alberta ear-cress was found at two new locations south collections of Halimolobos virgata and one of the Red Deer River near Bindloss (EO 6DVNDWFKHZDQFROOHFWLRQ¿OHGDWWKH8QLYHUVLW\ 029 and EO 030; Table 1). The extent of the of Calgary herbarium included dried-up stems subpopulation near McNeill (EO 010) was and remnants of pods from the previous year that extended northward to the proposed pipeline KDYH EHHQ UHLGHQWL¿HG DV Erysimum spp. (C. crossing of the South Saskatchewan River Bradley pers. obs., I. Macdonald pers. comm., about 7 km downstream of Sandy Point, based B. Smith pers. comm). All element occurrences on several new reports during the 2007 and documented by B. Smith included plants of the 2008 surveys (D. Bush pers. comm., C. Tannas current year except the two element occurrences pers. comm., A. Lees pers. comm.). in the Buffalo Atlee Pasture that were recorded solely on the basis of “old stems” (EO 006 and In 2008, four new occurrences of slender EO 032). These two element occurrences were mouse-ear-cress were reported during a targeted
10 survey in apparently suitable habitat (Bradley by drawing straight lines between the most 2008). One of these new occurrences is along northerly, westerly, southerly and easterly WKHQRUWKHUQERXQGDU\RI&)%6XI¿HOGDIHZ occurrences. A polygon that encompasses kilometres west of the Remount Pasture (EO only occurrences ranked as extant, including 018; Table 1). Another occurrence is a few mostly sand plain and choppy sand hills, is kilometres south of the Red Deer River between about 530 km2 in area (G. Berg pers. comm.). Cavendish and Buffalo (EO 015; Table 1), This area increases to 2930 km2 when all and two others are about 5 km apart south of RFFXUUHQFHVFRQVLGHUHGH[WDQWRUIDLOHGWR¿QG Empress and west of the South Saskatchewan are included, and 9998 km2 when all reported River where it loops into Saskatchewan (EO occurrences in Alberta (even those ranked as 016 and EO 017; Table 1). extirpated or historical) are included (G. Berg pers. comm.). At least half of the habitat within Over the last few decades, several rare plant the extant range (530 km2) of slender mouse- surveys have not reported any occurrences of ear-cress in Alberta has been converted to non- slender mouse-ear-cress in apparently suitable native vegetation and a considerable portion sand plain and river valley habitat in Alberta. of the native habitat is unsuitable including Slender mouse-ear-cress was not found in VKUXEODQGV ZHWODQGV DQG DONDOLQH ÀDWV WLOO extensive survey of sand hill and sand plain ridges, rolling sand dunes, eroding slopes and habitats of southern Alberta in 1987 (Wallis and rivers or streams. A similar proportion of the Wershler 1988). Neither was it found during range that includes all reported occurrences more recent rare plant surveys within the CFB (9998 km2) is unsuitable for slender mouse- 6XI¿HOG1DWLRQDO:LOGOLIH$UHD (OFKXN ear-cress. the Onefour Research Station (Bradley et al. 2006), the Many Island Lake area (C. Wallis 7KH NQRZQ DUHD RI RFFXSDQF\ GH¿QHG DV pers. comm.) and public lands leased to the the area within the extent of occurrence Drowning Ford Grazing Association and occupied by slender mouse-ear-cress excluding Hargraves Ranch (J. Lancaster pers. comm.). unsuitable or unoccupied habitat (IUCN 2001), During the last 10 years, rare plant surveys is estimated to be less than 0.05 km2 using data in other sand plain habitats of southeast from Alberta Natural Heritage Information Alberta conducted as part of environmental Centre (ANHIC) occurrence records. There are assessments for proposed pipeline routes or 33 unique locations of slender mouse-ear-cress JDV ¿HOG GHYHORSPHQWV KDYH UHVXOWHG LQ IHZ in ANHIC reports (based on UTM coordinates) if any, reports of slender mouse-ear-cress, and the maximum population extent for any even though the considerable search effort was one location is 1500 m2 (Table 1), implying targeted towards slender mouse-ear-cress and that area of occupancy for all known locations other priority species at risk (ASRD 2004 and is unlikely to exceed 0.05 km2 (33 x 1500 m2). 2008, J. Lancaster pers. comm., D. Bush pers. Slender mouse-ear-cress plants are found in comm.). In addition, systematic and intensive small discrete patches and seeds appear to fall VHDUFK HIIRUW LQ VSHFL¿FDOO\ RI KDELWDW close to the parent plants; hence area between considered to have high potential for slender patches is considered to be unoccupied. mouse-ear-cress, resulted in no occurrences in 14 of 18 quarter sections searched using Potential area of occupancy may also be parallel, randomly spaced transects (Bradley estimated to be less than 0.05 km2 if one applies 2008). the percentage area of suitable habitat occupied by slender mouse-ear-cress, derived from The extent of occurrence of slender mouse- results of the systematic 2008 survey, over the ear-cress is the area within a polygon made total extent of extant occurrences (530 km2).
11 Eighteen quarter sections with apparently In Montana, slender mouse-ear-cress was found suitable habitat were surveyed along up to ten in 1989 in the East Butte uplift of the Sweetgrass randomly-spaced, parallel transects in each Hills (SE6-36-5 E 5M), approximately 3 km quarter section (Bradley 2008). The sampling north/northeast of the summit of Mount approach gives an 80% to 90% probability of Brown and about 10 km south of the border detection, assuming an area of occupancy of with Alberta (Gray Herbarium 2009, Westech 0.1% of the study area (D. Henderson pers. 1989). This is within Liberty County about comm.). The total area occupied by the four 200 km south of McNeill. Collections from populations found in 2008 was 920 m2 out of Sheridan and Phillips counties in northeastern a total search area of approximately 11.5 km2; 0RQWDQD RULJLQDOO\ LGHQWL¿HG DV Halimolobos hence, only about 0.01% of apparently suitable virgataKDYHEHHQUHLGHQWL¿HGDVArabis hirsuta habitat searched was found to be occupied by (University of Montana Herbarium 2008). All slender mouse-ear-cress. other known Montana locations of slender mouse-ear-cress are a further 450 km south in The area of occupancy calculated by summing the Tendoy Mountains of Beaverhead County occupied1-km x 1-km squares (excluding failed- in the southwest part of the state (P. Lesica pers. WR¿QG H[WLUSDWHG DQG KLVWRULFDO RFFXUUHQFHV comm.). The nearest population in Wyoming results in an area of 18 km2 (or 52 km2 using is also 450 km south of the Sweetgrass Hills 2-km x 2-km squares, the International Union in the Absaroka Range of the northwest part of for Conservation of Nature standard [IUCN the state (University of Wyoming 1998). 2001] but less biologically relevant for this species). Elsewhere in the United States, slender mouse- ear-cress is known from northeastern Idaho 2. Other Areas – In Saskatchewan, slender (Butte county), central and western Wyoming mouse-ear-cress is known from 13 locations, (several counties), central Colorado (Gunnison plus three additional historical locations that and Park counties), northeastern Utah (Dagget have not been relocated (C. Neufeld pers. and Wasatch counties), southwest Nevada comm.) (Figure 2). Historical locations include (Esmeralda and Nye counties) and east one in Wood Mountain and two in the Cypress central California (Inyo and Mono counties) Hills. Extant populations occur north and west (NatureServe 2009, Al-Shehbaz in prep.) of the South Saskatchewan River between (Figure 2). Riverhurst and Outlook (Riverhurst, Birsay, Macrorie, Coteau, Lucky Lake), northeast of POPULATION SIZE AND TRENDS Kindersley (Stranraer), near Estuary on the South Saskatchewan River (Estuary, Alkali 1. Alberta – 7KHUH DUH LQVXI¿FLHQW GDWD WR Creek) and in the Great Sand Hills (Golden FRQ¿GHQWO\HVWLPDWHWKHVL]HRIWKHSURYLQFLDO Prairie, East Fox, Liebenthal). The closest population of slender mouse-ear-cress, in terms known location to Alberta is within the Prairie of number of individuals. Survey methods used National Wildlife Area Unit 20, approximately in acquiring existing data are generally not 45 km directly east of Alberta’s McNeill ZHOO GH¿QHG DQG OLNHO\ YDU\ JUHDWO\ WKHUHE\ location. Native prairie on sand plain contiguous confounding meaningful comparisons among with known habitat for slender mouse-ear-cress locations and years. With these provisos, a near McNeill appears to extend 10-15 km into population size of 3000–7000 individuals Saskatchewan; however, survey for slender is estimated based on the data currently mouse-ear-cress has not yet been conducted in available. this area (C. Neufeld pers. comm.).
12 Figure 2: Distribution of slender mouse-ear-cress in North America (based on information available from NatureServe 2009).
13 For slender mouse-ear-cress, an individual is and, in 2004, 184 individuals were reported in GH¿QHGE\DEDVDOOHDIURVHWWH5HSURGXFWLYH two clusters. In 2007, 251 individuals were SODQWV ZLOO KDYH D ÀRZHULQJ VKRRW RU VWHP reported in 11 clusters throughout a larger area associated with a basal rosette, whereas non- compared to previous surveys. From these reproductive plants will not. In addition, viable data one can estimate there are several hundred seeds in the soil are part of the non-reproductive (300–700) reproducing individuals in the population but are not readily counted. The McNeill subpopulation in a year with suitable PRVWSUDFWLFDODQGHI¿FLHQWXQLWIRUPRQLWRULQJ conditions for germination and growth, and population size of slender mouse-ear-cress is WKHUH DUH ODUJH ÀXFWXDWLRQV LQ WKH QXPEHU RI WKHÀRZHULQJVKRRW +HQGHUVRQ reproducing individuals from year to year.
The number of reproductive individuals within Data on the two southern Remount Pasture DVXESRSXODWLRQDVYDULRXVO\GH¿QHGLQUHSRUWV subpopulations (EO 003 and EO 007), along the ¿OHGZLWK$1+,&UDQJHVIURPWR 7DEOH ERXQGDU\ZLWK&)%6XI¿HOGFRQVLVWRIWKUHHWR 1, ANHIC 2008). The distribution of plants four records at each location (Table 1). Reports within known subpopulations (separated by no of size for the most easterly subpopulation (EO more than 3 km) varies from one small cluster 003) are, in 1997, 216 individuals in three of one or a few individuals to several scattered clusters; in 2002, no individuals; and, in 2004, clusters of several to many individuals. The 919 individuals in 1000 m2. Reported clusters three largest known subpopulations, in terms of are scattered over a 3-km distance, east to west. extent and size, are one north of McNeill and Reports of size for the second subpopulation east of the South Saskatchewan River (EO 010) (EO 007) are, in 1997 and 2002, no individuals; and two along the northeast boundary of CFB in 2007, 398 individuals in 1200 m2; and, in 6XI¿HOGLQWKH5HPRXQW3DVWXUH (2DQG 2008, 25 individuals in 400 m2. From these data EO 007). we can conclude that there are several hundred (300–700) individuals in each of the two There are more data for the McNeill Remount Pasture subpopulations, and perhaps subpopulation than any other subpopulation a few thousand (1000–3000) individuals in a (EO 010, Table 1). Data consist of reports of year with suitable conditions for germination slender mouse-ear cress at approximately 20 and growth. As well, there is evidence for unique sites (based on GPS coordinates provided ODUJHÀXFWXDWLRQVLQWKHQXPEHURIUHSURGXFLQJ by surveyors) over 11 years (1997–2008) (Table individuals from year to year. These two 1), in an area approximately 10 km by 3 km subpopulations are separated by approximately (30 km2) east of the South Saskatchewan River 3 km; however, the intervening habitat is to the Alberta-Saskatchewan border. Most of native grassland on sandy parent material the survey effort has been focused along two and additional survey may determine that the proposed pipeline rights-of-way and has not two subpopulations are one. Suitable habitat included a systematic approach to estimating for slender mouse-ear-cress also occurs a few total population size. Reported plant clusters hundred metres south of these subpopulations range in size from 1 individual to 150 individuals ZLWKLQ&)%6XI¿HOG KRZHYHUDPDMRUSLSHOLQH and in density from 36 individuals in 1114 m2 corridor, vehicle trail, fenceline and road bisect (0.03 plants/m2) to 39 individuals in 10 m2 what once was contiguous habitat. (3.9 plants/m2). The population size also varies over time. During a spring survey in 1997, 104 Another subpopulation (EO 015) of slender individuals were reported in three clusters; in mouse-ear-cress along the north boundary of 1999, only 12 individuals were reported at the &)%6XI¿HOGDQGZHVWRIWKH5HPRXQW3DVWXUH same sites; in 2002, no individuals were found; is separated from the nearest subpopulation
14 (2 E\¿YHNLORPHWUHVDQGDWLOOULGJH,Q 7KH GLVMXQFW VXESRSXODWLRQ (2 QHDU 2008, the only year of record, the subpopulation Matzhiwin Creek north of Duchess was was reported to have 47 individuals in 300 m2. characterized as having 54 individuals in ³VHYHUDOVPDOOSDWFKHVRYHUNP´ZKHQ¿UVW Two subpopulations (EO 029 and EO 030) about found in 1997 (Smith 2000). No slender mouse- NPQRUWKRI&)%6XI¿HOG¶VQRUWKHUQERXQGDU\ ear-cress has since been found during several near Bindloss have reported maximums of 130 searches at this location. This subpopulation and 96 individuals, respectively, in 2007, and is separated by over 160 km from the nearest much reduced numbers in 2008. These two subpopulations in the Remount Pasture. Much subpopulations are separated by 3 km, including of the intervening area is considered unsuitable a broad corridor of disturbance resulting habitat for slender mouse-ear-cress, given that from railway line and highway construction; VXU¿FLDOGHSRVLWVDUHQRWÀXYLDOHROLDQVDQGVEXW KHQFHWKHUHLVXQOLNHO\WREHVXI¿FLHQWJHQHWLF rather till, lacustrine silts and clays and eroded exchange between these two subpopulations to EHGURFNRIWKH'LQRVDXUEDGODQGV .MHDUVJDDUG consider them one. In 2008, about 15 km to and Pettapiece 1986). the west along Highway 555 near Cavendish, another subpopulation (EO 018) was reported Based on the data available, the provincial to have 87 individuals in a 600 m2 area. population of slender mouse-ear-cress is estimated to be in the order of several thousands A subpopulation (EO 005) of about 100 (3000–7000) of reproducing individuals in years individuals scattered in small clusters of 3–7 when conditions are suitable for germination stems over an area of about 200 m2 was reported DQG JURZWK 7R DFFXUDWHO\ GH¿QH SRSXODWLRQ in 1997. This subpopulation occurs on upland size and trends, known locations would need grassland west of the South Saskatchewan to be surveyed over a period of several years River near where a pipeline corridor crosses XVLQJ D ZHOOGH¿QHG PRQLWRULQJ SURWRFRO the river about 12 km upstream of the Highway GHVLJQHGWRPHHWDVSHFL¿HGGHJUHHRIVWDWLVWLFDO 41 bridge (Smith 2000, Smith pers. comm.). It FRQ¿GHQFHZLWKUHVSHFWWRSRSXODWLRQVL]HDQG is about 8 km west of McNeill and about 8 km extent (Elzinga et al. 1998, Henderson 2008). HDVW RI WKH &)% 6XI¿HOG¶V HDVWHUQ ERXQGDU\ As well, a systematic approach to searching for Two subsequent searches in the area failed to additional subpopulations would be required. ¿QGVOHQGHUPRXVHHDUFUHVV Environmental stochasticity and observation error pose challenges, as does the invisibility Three subpopulations are reported to have of the seed bank (Brigham and Thomson 2003, fewer than 20 individuals. A subpopulation Elderd et al. 2003, Alexander et al. 2009). (2 LQ&)%6XI¿HOGDERXWNPVRXWKRI the northern boundary was reported, in 1995, to 2. Other Areas – In Saskatchewan, the have 20 individuals in 375 m2. No individuals maximum population of slender mouse-ear- have been found there in two subsequent cress recorded at one of the 13 extant locations surveys. Two subpopulations (EO 016 and EO is 3678 individuals; four subpopulations are 017) south of Empress are reported, in 2008, reported to have 100–150 individuals; three to have only 7 and 15 reproducing individuals, have 20–40 individuals; three have fewer than respectively, and are separated by 5 km. The ¿YHLQGLYLGXDOV DQGWZRODFNFRXQWGDWDZLWK intervening habitat is native grassland on sandy no plants found in recent survey (C. Neufeld substrate; hence, additional search effort may pers. comm., Environment Canada 2009). ¿QGWKHVHWZRVXESRSXODWLRQVWREHRQH More systematic surveys for slender mouse- ear-cress in the Great Sand Hills in 2006, 2007 and 2008 are providing baseline data for more
15 FRQ¿GHQWO\ HVWLPDWLQJ SRSXODWLRQ VL]H DQG • Habitat for eight subpopulations of monitoring long-term trends. slender mouse-ear-cress has been altered ZLWKLQ WKH ODVW IHZ GHFDGHV E\ JDV ¿HOG DQG No information is available on population PDMRUSLSHOLQHFRUULGRUGHYHORSPHQW (2 size of slender mouse-ear-cress in the United EO 015, EO 007, EO 003, EO 029, EO 030, EO States. 005, EO 010). • As the amount of anthropogenic edge LIMITING FACTORS in native prairie increases, the potential for invasion of non-native species increases. /LPLWLQJ IDFWRUV DUH PDMRU IDFWRUV WKDW DIIHFW Invasion of non-native species, especially habitat quality and availability, reproductive crested wheat grass, from human disturbances output, or survival of individuals. The focus is adversely affecting the quality of slender is on factors that have an anthropogenic mouse-ear-cress habitat. origin. The effects of limiting factors may be cumulative. Further loss or alteration of habitat for slender mouse-ear-cress is predicted if current trends in 1. Loss and Degradation of Habitat – Loss of land use continue. native grasslands within the range of slender mouse-ear-cress continues to affect habitat Recently, the Joint Review Panel of the quality and availability. Native prairie decline Canadian Environmental Assessment Agency is caused primarily by agriculture expansion, and the Energy Resources Conservation Board urban development, oil and gas development recommended developing a management and the construction of transportation and utility strategy for non-native invasive plant species corridors, as well as the spread of invasive WRSURWHFWQDWLYHSUDLULHLQWHJULW\LQWKH6XI¿HOG non-native species in fragmented landscapes. National Wildlife Area (Joint Review Panel Information on loss of native grasslands within 2009). The National Wildlife Area includes slender mouse-ear-cress range is provided in known habitat for slender mouse-ear-cress. the Habitat section of this report. Key points The Joint Review Panel also recommended are summarized as follows: excluding industrial disturbance in critical • Over the last century, approximately habitat for slender mouse-ear-cress unless 50% of the Dry Mixedgrass Natural Subregion RWKHUZLVHVSHFL¿FDOO\SHUPLWWHG in southeast Alberta has been converted from native vegetation to a completely altered state 2. Anthropogenic Climate Change - Population by human land uses (Alberta Environmental GDWD VXJJHVW WKDW DQQXDO ZHDWKHU LQÀXHQFHV Protection 1997). germination and growth of slender mouse-ear- • Since 1970, in a study area that cress. For example, the absence of slender encompasses all of the provincial range of mouse-ear-cress rosettes and stems in 2002 extant slender mouse-ear-cress subpopulations, at locations where previously there had been bare ground resulting from agriculture many individuals may be explained by lower (cultivation) and industrial development has than average precipitation in May 2002; less increased 40% (from 10.2 ha/km2 to 14.3 ha/ than 10 mm measured at Empress and Bindloss km2) (Environment Canada 2008a). In the compared to an average of 40 mm (Environment same period linear disturbance has increased Canada 2008b). Relatively high numbers of 93% (from 2.7 km/km2 to 5.2 km/km2). individuals found in 2007 may be explained by • A subpopulation (EO 008) of slender higher than average precipitation in May 2007; mouse-ear-cress has been extirpated as a result 57 mm measured at Bindloss (Empress data not of municipal development. available). It can be assumed that predicted
16 change in climate because of human activities 3. Altered Fire Regime – $EVHQFH RI ¿UH will affect slender mouse-ear-cress reproduction may be affecting the slender mouse-ear-cress and survival, as well as its habitat. SRSXODWLRQ LQ $OEHUWD )RU PLOOHQQLD ¿UH started by lightning or humans was a constant Slender mouse-ear-cress occurs in that part of SUHVHQFHLQPL[HGJUDVVSUDLULHÀXFWXDWLQJZLWK $OEHUWDZLWKWKHKLJKHVWSRWHQWLDOIRUVLJQL¿FDQW regional climate change, vegetation change, and PRLVWXUH GH¿FLWV GXULQJ WKH JURZLQJ VHDVRQ cultural change. Fires ranged in size from less that is the Bindloss Plain Ecodistrict of the Dry than a hectare to several thousand hectares and Mixedgrass Natural Subregion. Predictions had return intervals from 0–35 years with mean are that this area will experience up to a 4°C intervals of 4–10 years (Henderson 2006). Fire increase in mean annual temperature by the helped to maintain a shifting mosaic of large 2020s, mostly occurring in winter and spring, ungulate grazing pressure on the landscape and and up to a 20% increase in mean annual played a role in soil organic matter formation. precipitation mostly occurring in winter and spring (Sauchyn and Kulshreshtha 2007); Such a pervasive disturbance in the ecosystem however, summers will be especially dry. A OLNHO\LQÀXHQFHGWKHHYROXWLRQDQGGLVWULEXWLRQ trend of increased aridity will most likely be of slender mouse-ear-cress. Fire may affect realized through a greater frequency of dry these and other herbaceous plants by reducing years. Also predicted are increased climate competition from perennial grasses and variability and more frequent extreme events, shrubs for space and resources, stimulating or LQFOXGLQJDJUHDWHUIUHTXHQF\RIÀRRGLQJDQG suppressing seed germination and sprouting of severe drought. dormant roots, enhancing growth by increasing organic matter in the soil, or directly killing Higher precipitation in spring may increase rosettes and reproductive shoots. germination and growth of slender mouse-ear- cress, especially if the species is associated with 7RGD\¿UHVXSSUHVVLRQLVSUDFWLFHGWKURXJKRXW vernal pools, although this has not yet been the range of slender mouse-ear-cress. Alteration FRQ¿UPHG ,QFUHDVHG VXPPHU GURXJKW PD\ RIWKH¿UHUHJLPHEH\RQGWKHUDQJHRIQDWXUDO negatively affect seed viability and survival of YDULDWLRQ LQ ¿UH DV DQ HFRV\VWHP SURFHVV LV plants that only appear as rosettes in a given likely resulting in more vegetation and litter year. The prairie population of slender mouse- cover and less bare soil in the mixedgrass ear-cress in Alberta and Saskatchewan has prairie habitats of slender mouse-ear-cress. survived drought in the past, including that of The implications for this species are unknown. the 1930s. However, occurrences in the United States (where most of the species’ range is) are Recently the Joint Review Panel of the at considerably higher elevations, 1000 m– Canadian Environmental Assessment Agency 3600 m, compared to elevations of 600 m– and the Energy Resources Conservation Board P LQ &DQDGD VXJJHVWLQJ DQ DI¿QLW\ WR recommended take measures “that are necessary cooler and moister growing season conditions DQGVDIH´WRUHVWRUHWKHQDWXUDO¿UHUHJLPHWR than are predicted for the mixedgrass prairie WKH 6XI¿HOG 1DWLRQDO :LOGOLIH $UHD ZKLFK region with climate change. includes known habitat for slender mouse-ear- cress (Joint Review Panel 2009). Movement of slender mouse-ear-cress northward as vegetation shifts in response 4. Altered Grazing Regime – For millennia, to climate change may be restricted by lack grazing by herbivores such as bison, pronghorn, of contiguous corridors and blocks of native elk, deer, small mammals and insects was a mixedgrass prairie on sandy substrates. constant presence in the prairie habitats of
17 slender mouse-ear-cress. Size, shape, spatial committee 2005). Slender mouse-ear-cress is distribution and the succession in grazed considered May Be At Risk according to the patches varied across the landscape over time, general status review (ASRD 2007). It is also depending on when, how long, how often and currently ranked as S1S2 in Alberta (Gould how intensively the mix of native herbivores 2006). JUD]HG(QYLURQPHQWDOPRGL¿FDWLRQVEURXJKW about by grazing animals contribute to variety 2. Other areas - Based on an assessment in habitats and biodiversity in the landscape by COSEWIC, slender mouse-ear-cress (Romo 2007). was designated Endangered in Canada in April 1992. Its status was re-evaluated and Such a pervasive disturbance in the ecosystem designated Threatened in Canada in May OLNHO\LQÀXHQFHGWKHHYROXWLRQDQGGLVWULEXWLRQ 2000 (Environment Canada 2009). It is of slender mouse-ear-cress. Grazing may affect listed on Schedule 1 of the federal 6SHFLHVDW herbaceous plants such as slender mouse-ear- 5LVN $FW (Government of Canada 2008). In cress by reducing competition from perennial Saskatchewan, slender mouse-ear-cress is grasses and shrubs for space and resources, ranked as S1 and is listed as Threatened under creating openings that stimulate or suppress the province’s :LOGOLIH $FW (Government of seed germination and sprouting of dormant Saskatchewan 2008). Nationally, in Canada roots, enhancing growth by increasing nutrients slender mouse-ear-cress has a rank of N2 in the soil, suppressing growth through soil (NatureServe 2009). A draft recovery strategy compaction, dispersing seed, or directly killing for slender mouse-ear-cress in Canada has rosettes and reproductive shoots through recently been developed (Environment Canada browsing and trampling. Today, slender mouse- 2009). ear-cress is found in areas that receive light to moderate livestock grazing pressure. In the United States, known locations of slender mouse-ear-cress are limited to one or a few In the 1800s, introduction of cattle meant going counties within each of the states in which it from an open system, where grazing patterns occurs (except for Wyoming). Slender mouse- ZHUH FOLPDWLFDOO\ GH¿QHG WR D FORVHG V\VWHP ear-cress is ranked as S1 in Utah, California and where management dictates pattern, timing Colorado, S3 in Montana and Wyoming, and and intensity of grazing. The implications SNR in Idaho and Nevada (NatureServe 2009, for slender mouse-ear-cress of this altered Al-Shehbaz in prep., B. Heidel pers. comm.). grazing regime, beyond the range of natural Detailed status evaluations of slender mouse- variation in grazing as an ecosystem process, HDUFUHVVZLWKLQWKHVHMXULVGLFWLRQVDUHODFNLQJ are unknown. Nationally, in the United States it is ranked as N3 and globally as G4 (NatureServe 2009). STATUS DESIGNATIONS* RECENT MANAGEMENT IN ALBERTA 1. Alberta – The evaluation of a detailed status report for slender mouse-ear-cress (ASRD 1R VSHFL¿F PDQDJHPHQW DFWLYLWLHV IRU WKH 2005) under the provincial Species At Risk protection of slender mouse-ear-cress have been Program resulted in an assessment of Data undertaken in Alberta. Because slender mouse- 'H¿FLHQW in 2005 (Alberta Endangered Species ear-cress is listed as Threatened in Schedule 1 &RQVHUYDWLRQ &RPPLWWHH 6FLHQWL¿F 6XE of the federal 6SHFLHV DW 5LVN $FW, provincial managers require that development proposals involving potential habitat on provincial land 6HH $SSHQGL[ IRU GH¿QLWLRQV RI VHOHFWHG VWDWXV designations. include rare plant surveys. If slender mouse-
18 ear-cress is found, steps must be taken to avoid $FW), and ensuring a monitoring program is adverse affects on the local subpopulation. implemented to evaluate the effects of the SURMHFW Provincial representatives have cooperated with representatives of Environment Canada, SYNTHESIS Agriculture and Agri-Food Canada and the Government of Saskatchewan in preparing a Slender mouse-ear-cress (Halimolobos national recovery strategy for slender-mouse- virgata (Nutt.) O.E. Schulz) is an annual, ear-cress through the National Recovery Team biennial or short-lived perennial herbaceous for Plants at Risk in the Prairie Provinces plant that recently has undergone taxonomic (Environment Canada 2009). Consultation is revision to Transberingia bursifolia subsp. occurring with Department of National Defence, virgata. In Alberta, slender mouse-ear-cress industry stakeholders, First Nations, and is found within the lower South Saskatchewan environmental non-government organizations. River and Red Deer River basins in the Dry 7KHVWUDWHJ\KDV\HWWREHRI¿FLDOO\DSSURYHG Mixedgrass Natural Subregion. Its habitat and implemented. is native grassland on silty to sandy parent PDWHULDORIJODFLRÀXYLDOÀXYLDORUHROLDQRULJLQ Slender mouse-ear-cress occurs along the on undulating to rolling sandy plain and river proposed route of the TransCanada Keystone valley slopes and terraces. Slender mouse-ear- 3LSHOLQHSURMHFW7KH1DWLRQDO(QHUJ\%RDUG cress appears to be associated with ephemerally 1(% DSSURYHG WKH SURMHFW LQ 6HSWHPEHU wet depressions and drainages. 2007. An environmental screening report FRPSOHWHG E\ WKH 1(% UHTXLUHV VSHFL¿F Fourteen subpopulations are recognized: one mitigation be developed, in consultation with is ranked as extirpated, one as historical, three Alberta Sustainable Resource Development and DV IDLOHGWR¿QG DQG QLQH DV H[WDQW ([WDQW Environment Canada, to minimize effects on occurrences are concentrated in the Bindloss rare plants, and that mitigation be incorporated Plain Ecodistrict. The historical extent of into the Environmental Protection Plan and the occurrence of all subpopulations is about Operations Vegetation Management Plan for 9998 km2; that of only extant ones is about WKHSURMHFW 1DWLRQDO(QHUJ\%RDUG 530 km2. Area of occupancy estimated from element occurrence data is less than 0.05 km2; There is one occurrence of slender mouse- calculated by summing occupied 1-km x 1-km HDUFUHVV UHFRUGHG LQ WKH &)% 6XI¿HOG squares results in an area of occupancy of 18 National Wildlife Area, an area managed by km2. Substantial rare plant search effort over the Department of National Defence with the last few decades, and particularly within the advice from the Canadian Wildlife Service of last few years, has resulted in reports of only a Environment Canada. A proposed shallow few localized subpopulations of slender mouse- JDVLQ¿OOGHYHORSPHQWSURMHFWLQWKH1DWLRQDO ear-cress within apparently suitable habitat. :LOGOLIH $UHD ZDV UHFHQWO\ WKH VXEMHFW RI D panel review of the Canadian Environmental Estimates of reproducing individuals of slender Assessment Agency and the Energy Resources mouse-ear cress at the 14 known occurrences Conservation Board. The report of the Joint range from 1 to 919 plants, and data over Review Panel (2009) includes recommendations multiple years at some sites suggest large IRU¿QDOL]LQJFULWLFDOKDELWDWRIVOHQGHUPRXVH ÀXFWXDWLRQV GHSHQGLQJ RQ HQYLURQPHQWDO ear-cress, using mapped critical habitat as conditions such as timing and amount of rainfall H[FOXVLRQDUHDVLIWKHSURMHFWSURFHHGV XQOHVV in spring. The provincial population of slender otherwise permitted under the 6SHFLHVDW5LVN mouse-ear-cress is estimated to be in the order
19 of several thousand (3000–7000) reproductive additional subpopulations will be required individuals in years when conditions are similar to that used by Bradley (2008). suitable for germination and growth. Alberta’s extant population of slender mouse- Loss of native grasslands within the range of ear-cress is approximately 45 km from the slender mouse-ear-cress continues to affect closest known subpopulation in Saskatchewan habitat quality and availability. Native prairie and 200 km from the nearest population in decline is caused primarily by agriculture Montana. No genetic exchange is expected. expansion, urban development, oil and Future survey is needed to determine if there gas development and the construction of is a subpopulation in Saskatchewan contiguous transportation and utility corridors, as well with the McNeill subpopulation in Alberta. In as the spread of invasive non-native species addition, more taxonomic investigation of the in fragmented landscapes. Since 1970, bare prairie population of slender mouse-ear-cress ground resulting from agriculture (cultivation) is suggested to ascertain the degree to which and industrial development has increased 40% there are features distinct from populations of and linear disturbance has increased 93% in a slender mouse-ear-cress several hundreds of study area that encompasses all of the range of kilometres to the north and to the southwest extant slender mouse-ear-cress subpopulations. (Environment Canada 2009). Other potential limiting factors are climate FKDQJH DQG DOWHUHG ¿UH DQG JUD]LQJ UHJLPHV Slender mouse-ear-cress was designated as beyond the range of natural variation. Endangered by COSEWIC in 1992 and re- assessed as Threatened in 2000. It is listed on 7R DFFXUDWHO\ GH¿QH SRSXODWLRQ VL]H H[WHQW Schedule 1 of the federal 6SHFLHVDW5LVN$FW. and trends, known locations will need to be In Saskatchewan, slender mouse-ear-cress surveyed over a period of several years using is listed as Threatened under the province’s DZHOOGH¿QHGPRQLWRULQJSURWRFROGHVLJQHGWR :LOGOLIH $FW. A draft recovery strategy for PHHWDVSHFL¿HGGHJUHHRIVWDWLVWLFDOFRQ¿GHQFH slender mouse-ear-cress in Canada has recently with respect to population size and extent. As been developed. well, a systematic approach to searching for
20 LITERATURE CITED Alberta Natural Heritage Information Centre (ANHIC). 2005. Natural Regions and Adams, B.W., L. Poulin-Klein, D. Moisey, Subregions of Alberta. URL: http://tpr. and R.L. McNeil. 2005. Rangeland alberta.ca/parks/heritageinfocentre/ Plant Communities and Range Health naturalregions/ [Updated: June 2005]. Assessment Guidelines of the Dry Mixedgrass Natural Subregion of ANHIC. 2007. Explanation of ranks. Alberta Alberta. Rangeland Management Tourism, Parks, Recreation and Branch, Public Lands Division, Alberta Culture. URL: http://tprc.alberta. Sustainable Resource Development, ca/parks/heritageinfocentre/animals/ Lethbridge, Pub. No. T/040. 106 pp. GH¿QLWLRQVDVS[ >8SGDWHG 2FWREHU 2007]. Al-Shehbaz, I.A. in prep. Flora of North America (FNA) Draft Treatment of ANHIC. 2008. Element occurrence records Transberingia bursifolia (including for slender mouse-ear-cress, December subsp. virgata). 2 pp. 23, 2008.
Al-Shehbaz, I.A., and S.L. O’Kane. 2003. Alberta Prairie Conservation Forum. 2000. Transberingia, a new generic name Native prairie baseline vegetation replacing the illegitimate Beringia inventory. URL: http://www. (Brassicaceae). Novon 13:396. albertapcf.org/background.htm [Accessed: February 25, 2009] Alberta Endangered Species Conservation &RPPLWWHH 6FLHQWL¿F 6XEFRPPLWWHH Alberta Sustainable Resource Development 2005. Status Evaluation for Slender (ASRD). 2001. The General Status Mouse-ear-cress (Halimolobos virgata) of Alberta Wild Species 2000. Alberta in Alberta. 3 pp. Sustainable Resource Development, Fish and Wildlife Service. Edmonton, Alberta Environmental Protection. 1996. AB. 46 pp. The Status of Alberta Wildlife. Alberta Environmental Protection, ASRD. 2004. Status of the Tiny Cryptanthe Natural Resources Service, Wildlife (Cryptantha minima) in Alberta. Management Division. Edmonton, Alberta Sustainable Resource AB. 44 pp. Development, Fish and Wildlife Division, and Alberta Conservation Alberta Environmental Protection. 1997. The Association. Wildlife Status Report Grassland Natural Region of Alberta: No. 54. Edmonton, AB. 39 pp. One of a Series of Reports Prepared for the Special Places 2000 Provincial ASRD. 2005. Status of the Slender Mouse- Coordinating Committee. 229 pp. plus ear-cress (Halimolobos virgata) in maps. Alberta. Alberta Sustainable Resource Development, Fish and Wildlife Alberta Forestry, Lands and Wildlife. 1991. Division, and Alberta Conservation The Status of Alberta Wildlife. Alberta Association. Wildlife Status Report Forestry, Lands and Wildlife, Fish and No. 55. Edmonton, AB. 27 pp. Wildlife Division. Edmonton, AB. 49 pp.
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22 of Endangered Wildlife in Canada. http://www.climate.weatheroffice. Ottawa, ON. vi + 18 pp. ec.gc.ca. [Date accessed: February 18, 2009] &26(:,& 'H¿QLWLRQVDQGDEEUHYLDWLRQV Committee on the Status of Endangered Environment Canada. 2009. Proposed Wildlife in Canada. URL: http://www. Recovery Strategy for Slender Mouse- cosewic.gc.ca/eng/sct2/sct2_6_e.cfm ear-cress (Halimolobos virgata) in [Updated: June 2009]. Canada (Proposed, January 2009). Species at Risk Act Recovery Series. Elchuk, C. 2005. Survey for Slender Mouse- ear-cress (Halimolobos virgata), CFB- Gauthier, D.A., A. Lafon, T.P. Toombs, J. Hoth, 6XI¿HOG1:$-XQH 5HSRUWRI and E. Wiken. 2003. Grasslands: Results. Prepared for Department of Toward a North American Conservation 1DWLRQDO 'HIHQFH &)% 6XI¿HOG Strategy. Canadian Plains Research pp. Center, University of Regina, Regina, Saskatchewan and Commission for Elderd, B.D., P. Shahani, and D.F. Doak. 2003. Environmental Cooperation, Montreal, The problems and potential of count- PQ. 99 pp. based population viability analyses. pp. 173-202 in C. A. Brigham and Gould, J. 2006. Alberta Natural Heritage M.W. Schwartz (eds.). Population Information Centre Tracking and Viability in Plants: Conservation, Watch Lists–Vascular Plants, Mosses, Management and Modeling of Rare Liverworts and Hornworts. Alberta Plants. Ecological Studies 165. Community Development, Parks and Springer-Verlag Berlin Heidelberg. Protected Areas Division, Edmonton, Alberta. On-line edition URL: http:// Elzinga, C.L., D.W. Salzer, and J.W. www.cd.gov.ab.ca/preserving/parks/ Willoughby. 1998. Measuring and anhic/index.asp. [Accessed: December Monitoring Plant Populations. BLM 18, 2008]. Technical Reference 1730-1. Denver, CO. 477 pp. Government of Canada. 2008. Species at risk public registry. URL: http:// Environment Canada. 2008a. Appendix H: www.sararegistry.gc.ca. [Accessed: Cumulative environmental effects. December 18, 2008] pp. 293-318 in Submission of the Department of the Environment Government of Saskatchewan. 2008. (Environment Canada) to the Canadian Interim List for Species at Risk in Environmental Assessment Agency Saskatchewan. URL: http://www. Alberta Energy and Utilities Board environment.gov.sk.ca [Date accessed: Joint Panel Hearing of the EnCana December 18, 2008]. &RUSRUDWLRQ ,Q¿OO 'ULOOLQJ 3URMHFW Ottawa. Gray Herbarium. 2009. Index of botanical specimens. Collection 246362. URL: Environment Canada. 2008b. Monthly data http://asaweb.huh.harvard.edu:8080/ reports for Empress and Bindloss databases/specimens [Accessed: weather stations. National climate and February 15, 2009]. weather information archive. URL:
23 Great Sand Hills Advisory Committee. IUCN. 2001. IUCN Red List Categories and 2007. Great Sand Hills Regional Criteria: Version 3.1. IUCN Species Environmental Study. Prepared for Survival Commission. IUCN, Gland, Government of Saskatchewan. Regina, Switzerland and Cambridge,UK. ii + SK. 229 pp. 30 pp.
Hammerson, G. A., D. Schweitzer, L. Master, Integrated Taxonomic Information System. and J. Cordeiro. 2008. Ranking species 2009. Halimolobos virgata. URL: occurrences - a generic approach. http://www.itis.gov/index.html NatureServe. Arlington, Virginia. [Accessed: January 14, 2009] URL: http://www.natureserve.org/ explorer/eorankguide. [Accessed: Joint Review Panel. 2009. Report of the February 1, 2009]. Joint Review Panel Established by the Federal Minister of the Environment Heidinga, L., and S.D. Wilson. 2002. The and the Alberta Energy and Utilities impact of an invading alien grass Board Decision 2009-008: EnCana ($JURS\URQ FULVWDWXP) on species 6KDOORZ *DV ,Q¿OO 'HYHORSPHQW turnover in native prairie. Diversity 3URMHFW 3XEOLVKHG E\ (QHUJ\ and Distributions 8(5):249-258. Resources Conservation Board and Canadian Environmental Assessment Henderson, D. 2006. Background for Fire Agency Reference No. 05-07-15620 Management Plan for Grasslands (January 27, 2009), Ottawa, ON. 198 National Park. Parks Canada. pp. Grasslands National Park, SK. 15 pp. Jordan, N.R., D.L.Larson, and S.C.Huerd. Henderson, D. 2007. Crested Wheatgrass 6RLO PRGL¿FDWLRQ E\ LQYDVLYH ,QYDVLRQ ,QÀXHQFH RI 3UHYDLOLQJ plants: Effects on native and invasive :LQGVDQG*UD]LQJDW6XI¿HOG1DWLRQDO species of mixed-grass prairies. Wildlife Area. Environment Canada – Biological Invasions 10(2):177-190. Canadian Wildlife Service. Saskatoon, SK. 7 pp. Kershaw, L., J. Gould, D. Johnson, and J. Lancaster (eds). 2001. Rare Vascular Henderson, D. 2008. Occupancy Survey Plants of Alberta. University of Alberta Guidelines: Prairie Plant Species at Press and Canadian Forest Service, Risk (Draft 2). Environment Canada – Edmonton, AB. 484 pp. Canadian Wildlife Service. Saskatoon, SK. 36 pp. .MHDUVJDDUG$$DQG::3HWWDSLHFH Soils of the Medicine Hat area (72L). Henderson, D.C., and M.A. Naeth. 2005. Multi- Agriculture Canada Research Branch, scale impacts of crested wheatgrass Land Resource Research Centre, invasion in mixed-grass prairie. Edmonton AB. Map scale 1:126 720. Biological Invasions 7(4):639-650. LRRC contributions 90-24 to 90-27.
Holmgren, N.H., P.K. Holmgren, and A. Macdonald, I.D. 1997. Vascular Plant Flora Cronquist. 2005. Vascular plants Component Report – Canadian Forces of the Intermountain West, U.S.A., %DVH 6XI¿HOG 1DWLRQDO :LOGOLIH$UHD subclass Dilleniidae. Intermountain Inventory. Canadian Wildlife Service, Flora 2(B):1-488. Environment Canada, Prairie and 24 Northern Region. Edmonton, AB. vi 2004 Working Group, NatureServe, + 209 pp. Arlington, Virginia.
Macdonald, I.D. 2002. Status of Slender Mouse- NatureServe. 2009. NatureServe Explorer: ear-cress (Halimolobos virgata) in An online encyclopedia of life [web Alberta: Report on the On-site Survey application]. Version 7.1. Arlington, Phase (June 2002). Prepared for Virginia, USA: NatureServe. URL: Canadian Wildlife Service, Saskatoon, http://www.natureserve.org/explorer SK. 10 pp. [Updated: 17 July 2009].
Montana Field Guide. 2008. URL: Prairie Conservation Forum. 2008. Prairie http://FieldGuide.mt.gov/detail_ Environment Series: Grassland PDBRA1A040.aspx [Accessed: Cumulative Effects. Presentation. December 18, 2008] URL: http://www.albertapcf.org [Updated: February 12, 2008.]. Moss, E.H. 1983. Flora of Alberta. Second edition, revised by John G. Packer. Price, R.A., I.A. Sl-Shehbaz, and S.L. O’Kane. University of Toronto Press, Toronto, 2001. Beringia (Brassicaceae), a new Canada. 687 pp. JHQXVRI$UDELGRSVRLGDI¿QLWLHVIURP Russia and North America. Novon National Energy Board. 2007. Reasons for 11:332-336. Decision TransCanada Keystone Pipeline GP Ltd. OH-1-2007. URL: 5RPR -7 %HQH¿FLDO 0DQDJHPHQW https://www.neb-one.gc.ca/ [Accessed: Practices for Conservation Grazing to May 10, 2009] Enhance Biological Diversity on Native Prairie. Prepared for Agriculture and National Park Service, U.S. Department Agri-Food Canada. 28 pp. of Interior. 2003. Leafy Spurge – Integrated Pest Management Manual. Rowland, J. 2008. Ecosystem Impacts of URL: http://www.nature.nps.gov/ Historical Shallow Gas Wells Within biology/ipm/manual/spurge.cfm. WKH &)% 6XI¿HOG 1DWLRQDO :LOGOLIH [Accessed: January 21, 2009] Area. Director General Environment, Department of National Defence. 33 National Research Council. 1995. Science and pp. the Endangered Species Act. National Academy Press, Washington, DC. 271 Sauchyn, D., and S. Kulshreshtha. 2007. The pp. Prairies, in From Impacts to Adaptation: Canada in a Changing Climate 2007. Natural Regions Committee. 2006. Natural Edited by D. Lemmen F.J. Warren, J., Regions and Subregions of Alberta. Lacroix and E. Bush. Government of Compiled by D.J. Downing and W.W. Canada, Ottawa. Pettapiece. Government of Alberta. Pub. No. I/005. Smith, B.M. 1992. COSEWIC Status Report on the Slender Mouse-ear-cress NatureServe. 2004. A Habitat-Based (Halimolobos virgata) in Canada. Strategy for Delimiting Plant Element Committee on the Status of Endangered Occurrences: Guidance from the
25 Wildlife in Canada. Ottawa, ON. 39 6XI¿HOG 'HSDUWPHQW RI 1DWLRQDO pp. 'HIHQFH&)%6XI¿HOG$%SS
Smith, B.M. 2000. Update COSEWIC Status University of Montana Herbarium. 2008. Report on the Slender Mouse-ear-cress Montana vascular plant database. (Halimolobos virgata) in Canada, in URL: http://herbarium.dbs.umt.edu/. COSEWIC Assessment and Update [Accessed: December 22, 2008]. Status Report on the Slender Mouse- ear-cress (Halimolobos virgata) in University of Wyoming, Rocky Mountain Canada. Committee on the Status Herbarium. 1998. Atlas of the Vascular of Endangered Wildlife in Canada. Flora of Wyoming, Halimolobos Ottawa, ON. 18 pp. virgata. URL:http://www.sbs.utexas. edu/tchumley/wyomap/atlas.htm. Smith, B. 2007. Assessment of Agronomic [Updated: 10 August 1998]. Species Invasion from Pipeline Rights- RIZD\ DW &)% 6XI¿HOG 1DWLRQDO Wallis, C., and C. Wershler. 1988. Rare Wildlife Wildlife Area. Department of National and Plant Conservation Studies in 'HIHQFH&)%6XI¿HOG$%SS Sand Hill and Sand Plain Habitats of Southern Alberta. Alberta Forestry, Smith, B., and A. Taylor. 2007. Assessment Lands and Wildlife, Alberta Recreation of Residual Crested Wheatgrass and Parks and World Wildlife Fund ($JURS\URQ FULVWDWXP) Lease Site Canada. 161 pp. Footprint and Invasion From Old Pipelines to New Pipelines. Department Westech. 1989. Rare Plant Inventory and RI 1DWLRQDO 'HIHQFH &)% 6XI¿HOG Plant Community Descriptions of AB. 25 pp. the Sweetgrass Hills Proposed Area of Critical Environmental Concern, Smith, B., and M. Tulis. 2007. GIS Analysis of Toole and Liberty Counties, Montana. the Footprint of Minimal Disturbance Unpublished report to USDI Bureau of Shallow Gas Development at CFB Land Management. Great Falls MT. 36 pp. plus appendices.
26 Appendix 1: Definitions of status ranks and legal designations.
A. The General Status of Alberta Wild Species 2005 (after Alberta Sustainable Resource Development 2007)
2005 Rank 1996 Rank Definitions At Risk Red Any species known to be At Risk after formal detailed status assessment and designation as Endangered or Threatened in Alberta. May Be At Risk Blue Any species that may be at risk of extinction or extirpation, and is therefore a candidate for detailed risk assessment. Sensitive Yellow Any species that is not at risk of extinction or extirpation but may require special attention or protection to prevent it from becoming at risk. Secure Green Any species that is not At Risk, May Be At Risk or Sensitive. Undetermined Status Any species for which insufficient information, knowledge or data Undetermined is available to reliably evaluate its general status. Not Assessed n/a Any species that has not been examined during this exercise. Exotic/Alien n/a Any species that has been introduced as a result of human activities. Extirpated/Extinct n/a Any species no longer thought to be present in Alberta (Extirpated) or no longer believed to be present anywhere in the world (Extinct). Accidental/Vagrant n/a Any species occurring infrequently and unpredictably in Alberta, i.e., outside its usual range.
B. Alberta Species at Risk Formal Status Designations Species designated as Endangered under Alberta’s Wildlife Act include those listed as Endangered or Threatened in the Wildlife Regulation (in bold).
Endangered A species facing imminent extirpation or extinction. Threatened A species likely to become endangered if limiting factors are not reversed. Species of A species of special concern because of characteristics that make it particularly sensitive to Special Concern human activities or natural events. Data Deficient A species for which there is insufficient scientific information to support status designation.
C. Committee on the Status of Endangered Wildlife in Canada (after COSEWIC 2009)
Extinct A species that no longer exists. Extirpated A species that no longer exists in the wild in Canada, but occurs elsewhere. Endangered A species facing imminent extirpation or extinction. Threatened A species that is likely to become endangered if nothing is done to reverse the factors leading to its extirpation or extinction. Special Concern A species that may become threatened or endangered because of a combination of biological characteristics and identified threats. Not at Risk A species that has been evaluated and found to be not at risk of extinction given the current circumstances. Data Deficient A category that applies when the available information is insufficient to (a) resolve a wildlife species' eligibility for assessment, or (b) permit an assessment of the wildlife species' risk of extinction.
27 D. Heritage Status Ranks: Global (G), National (N), Sub-national (S) (after Alberta Natural Heritage Information Centre 2007, NatureServe 2009)
G1/N1/S1 5 or fewer occurrences or only a few remaining individuals. May be especially vulnerable to extirpation because of some factor of its biology. G2/N2/S2 6 to 20 or fewer occurrences or with many individuals in fewer locations. May be especially vulnerable to extirpation because of some factor of its biology. G3/N3/S3 21 to 100 occurrences; may be rare and local throughout its range, or in a restricted range (may be abundant in some locations). May be susceptible to extirpation because of large- scale disturbances. G4/N4/S4 Typically > 100 occurrences. Apparently secure. G5/N5/S5 Typically > 100 occurrences. Demonstrably secure. GX/NX/SX Believed to be extinct or extirpated; historical records only. GH/NH/SH Historically known; may be relocated in the future. G?/N?/S? Not yet ranked, or rank tentatively assigned.
E. United States Endangered Species Act (after National Research Council 1995)
Endangered Any species that is in danger of extinction throughout all or a significant portion of its range. Threatened Any species that is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.
28 List of Titles in This Series (as of August 2009)
No. 1 Status of the Piping Plover (Charadrius melodus) in Alberta, by David R. C. Prescott. 19 pp. (1997)
No. 2 Status of the Wolverine (Gulo gulo) in Alberta, by Stephen Petersen. 17 pp. (1997)
No. 3 Status of the Northern Long-eared Bat (Myotis septentrionalis) in Alberta, by M. Carolina Caceres and M. J. Pybus. 19 pp. (1997)
No. 3 Update 2009. Status of the Northern Myotis (Myotis septentrionalis) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 34 pp. (2009)
No. 4 Status of the Ord’s Kangaroo Rat (Dipodomys ordii) in Alberta, by David L. Gummer. 16 pp. (1997)
No. 5 Status of the Eastern Short-horned Lizard (Phrynosoma douglassii brevirostre) in Alberta, by Janice D. James, Anthony P. Russell and G. Lawrence Powell. 20 pp. (1997)
No. 5 Update 2004. Status of the Short-horned Lizard (Phrynosoma hernandesi) in Alberta. Alberta Sustainable Resource Development. 27 pp. (2004)
No. 6 Status of the Prairie Rattlesnake (Crotalus viridis viridis) in Alberta, by Sheri M. Watson and Anthony P. Russell. 26 pp. (1997)
No. 7 Status of the Swift Fox (Vulpes velox) in Alberta, by Susan E. Cotterill. 17 pp. (1997)
No. 8 Status of the Peregrine Falcon (Falco peregrinus anatum) in Alberta, by Petra Rowell and David P. Stepnisky. 23 pp. (1997)
No. 9 Status of the Northern Leopard Frog (Rana pipiens) in Alberta, by Greg Wagner. 46 pp. (1997)
No. 9 Update 2003. Status of the Northern Leopard Frog (Rana pipiens) in Alberta. Alberta Sustainable Resource Development. 61 pp. (2003)
No. 10 Status of the Sprague’s Pipit (Anthus spragueii) in Alberta, by David R. C. Prescott. 14 pp. (1997)
No. 11 Status of the Burrowing Owl (Speotyto cunicularia hypugaea) in Alberta, by Troy I. Wellicome. 21 pp. (1997)
No. 11 Update 2005. Status of the Burrowing Owl (Athene cunicularia) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 28 pp. (2005)
No. 12 Status of the Canadian Toad (Bufo hemiophrys) in Alberta, by Ian M. Hamilton, Joann L. Skilnick, Howard Troughton, Anthony P. Russell, and G. Lawrence Powell. 30 pp. (1998)
No. 13 Status of the Sage Grouse (Centrocercus urophasianus urophasianus) in Alberta, by Cameron L. Aldridge. 23 pp. (1998)
No. 14 Status of the Great Plains Toad (Bufo cognatus) in Alberta, by Janice D. James. 26 pp. (1998)
No. 15 Status of the Plains Hognose Snake (Heterodon nasicus nasicus) in Alberta, by Jonathan Wright and Andrew Didiuk. 26 pp. (1998)
No. 16 Status of the Long-billed Curlew (Numenius americanus) in Alberta, by Dorothy P. Hill. 20 pp. (1998) No. 17 Status of the Columbia Spotted Frog (Rana luteiventris) in Alberta, by Janice D. James. 21 pp. (1998)
No. 18 Status of the Ferruginous Hawk (Buteo regalis) in Alberta, by Josef K. Schmutz. 18 pp. (1999)
No. 18 Update 2006. Status of the Ferruginous Hawk (Buteo regalis) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 22 pp. (2006)
No. 19 Status of the Red-tailed Chipmunk (7DPLDVUX¿FDXGXV) in Alberta, by Ron Bennett. 15 pp. (1999)
No. 20 Status of the Northern Pygmy Owl (Glaucidium gnoma californicum) in Alberta, by Kevin C. Hannah. 20 pp. (1999)
No. 21 Status of the Western Blue Flag (Iris missouriensis) in Alberta, by Joyce Gould. 22 pp. (1999)
No. 21 Update 2005. Status of the Western Blue Flag (Iris missouriensis) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 29 pp. (2005)
No. 22 Status of the Long-toed Salamander (Ambystoma macrodactylum) in Alberta, by Karen L. Graham and G. Lawrence Powell. 19 pp. (1999)
No. 23 Status of the Black-throated Green Warbler (Dendroica virens) in Alberta, by Michael R. Norton. 24 pp. (1999)
No. 24 Status of the Loggerhead Shrike (Lanius ludovicianus) in Alberta, by David R. C. Prescott and Ronald R. Bjorge. 28 pp. (1999)
No. 25 Status of the Plains Spadefoot (Spea bombifrons) in Alberta, by Richard D. Lauzon. 17 pp. (1999)
No. 26 Status of the Trumpeter Swan (Cygnus buccinator) in Alberta, by M. Lynne James. 21 pp. (2000)
1R 6WDWXVRIWKH3\JP\:KLWH¿VK Prosopium coulteri) in Alberta, by William C. Mackay. 16 pp. (2000)
No. 28 Status of the Short-eared Owl ($VLRÀDPPHXV) in Alberta, by Kort M. Clayton. 15 pp. (2000)
No. 29 Status of the Willow Flycatcher (Empidonax traillii) in Alberta, by Bryan Kulba and W. Bruce McGillivray. 15 pp. (2001)
No. 30 Status of the Woodland Caribou (Rangifer tarandus caribou) in Alberta, by Elston Dzus. 47 pp. (2001)
No. 31 Status of the Western Spiderwort (Tradescantia occidentalis) in Alberta, by Bonnie Smith. 12 pp. (2001)
No. 32 Status of the Bay-breasted Warbler (Dendroica castanea) in Alberta, by Michael Norton. 21 pp. (2001)
No. 33 Status of the Cape May Warbler (Dendroica tigrina) in Alberta, by Michael Norton. 20 pp. (2001)
No. 34 Status of the Whooping Crane (Grus americana) in Alberta, by Jennifer L. White. 21 pp. (2001)
No. 35 Status of Soapweed (Yucca glauca) in Alberta, by Donna Hurlburt. 18 pp. (2001)
No. 36 Status of the Harlequin Duck (Histrionicus histrionicus) in Alberta, by Beth MacCallum. 38 pp. (2001)
No. 37 Status of the Grizzly Bear (Ursus arctos) in Alberta, by John L. Kansas. 43 pp. (2002)
No. 38 Status of the Wood Bison (Bison bison athabascae) in Alberta, by Jonathan A. Mitchell and C. Cormack Gates. 32 pp. (2002) No. 39 Status of the Bull Trout (6DOYHOLQXVFRQÀXHQWXV) in Alberta, by John R. Post and Fiona D. Johnston. 40 pp. (2002)
No. 40 Status of the Banff Springs Snail (Physella johnsoni) in Alberta, by Dwayne A.W. Lepitzki. 29 pp. (2002)
No. 41 Status of the Shortjaw Cisco (Coregonus zenithicus) in Alberta, by Mark Steinhilber. 23 pp. (2002)
No. 42 Status of the Prairie Falcon (Falco mexicanus) in Alberta, by Dale Paton. 28 pp. (2002)
No. 43 Status of the American Badger (Taxidea taxus) in Alberta, by Dave Scobie. 17 pp. (2002)
No. 44 Status of the Yucca Moth (Tegeticula yuccasella) in Alberta. Alberta Sustainable Resource Development. 21 pp. (2002)
No. 45 Status of the White-winged Scoter (Melanitta fusca deglandi) in Alberta. Alberta Sustainable Resource Development. 15 pp. (2002)
No. 46 Status of the Lake Sturgeon (Acipenser fulvescens) in Alberta. Alberta Sustainable Resource Development. 30 pp. (2002)
No. 47 Status of the Western Silvery Minnow (Hybognathus argyritis) in Alberta. Alberta Sustainable Resource Development. 24 pp. (2003)
1R 6WDWXVRIWKH6PDOOÀRZHUHG6DQG9HUEHQD Tripterocalyx micranthus) in Alberta. Alberta Sustainable Resource Development. 24 pp. (2003)
No. 49 Status of the Brown Creeper (Certhia americana) in Alberta. Alberta Sustainable Resource Development. 30 pp. (2003)
No. 50 Status of the Mountain Plover (Charadrius montanus) in Alberta. Alberta Sustainable Resource Development. 25 pp. (2003)
No. 51 Status of the St. Mary Shorthead Sculpin (provisionally Cottus bairdi punctulatus) in Alberta. Alberta Sustainable Resource Development. 24 pp. (2003)
No. 52 Status of the Stonecat (1RWXUXVÀDYXV) in Alberta. Alberta Sustainable Resource Development. 22 pp. (2003)
No. 53 Status of the Sage Thrasher (Oreoscoptes montanus) in Alberta. Alberta Sustainable Resource Development. 23 pp. (2004)
No. 54 Status of the Tiny Cryptanthe (Cryptantha minima) in Alberta. Alberta Sustainable Resource Development. 39 pp. (2004)
No. 55 Status of the Slender Mouse-ear-cress (Halimolobos virgata) in Alberta. Alberta Sustainable Resource Development. 27 pp. (2005)
No. 55 Update 2009. Status of the Slender Mouse-ear-cress (Halimolobos virgata or Transberingia bursifolia subsp. virgata) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 28 pp. (2009)
No. 56 Status of the Barred Owl (Strix varia) in Alberta. Alberta Sustainable Resource Development. 15 pp. (2005)
No. 57 Status of the Arctic Grayling (Thymallus arcticus) in Alberta. Alberta Sustainable Resource Development. 41 pp. (2005) No. 58 Status of the Weidemeyer’s Admiral (Limenitis weidemeyerii) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 13 pp. (2005)
No. 59 Status of the Porsild’s Bryum (Bryum porsildii) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 30 pp. (2006)
No. 60 Status of the Western Grebe (Aechmophorus occidentalis) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 29 pp. (2006)
No. 61 Status of the Westslope Cutthroat Trout (Oncorhynchus clarkii lewisii) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 34 pp. (2006)
No. 62 Status of the Limber Pine (3LQXVÀH[LOLV) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 17 pp. (2007)
No. 63 Status of the Whitebark Pine (Pinus albicaulis) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 22 pp. (2007)
No. 64 Status of the Western Small-footed Bat (Myotis ciliolabrum) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 24 pp. (2008)
1R 6WDWXVRIWKH9HUQD¶V)ORZHU0RWK Schinia verna) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 17 pp. (2008)
No. 66 Status of the Athabasca Rainbow Trout (Oncorhynchus mykiss) in Alberta. Alberta Sustainable Resource Development and Alberta Conservation Association. 32 pp. (2009)