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Final Report To Tembec Industries Inc. December 1, 2008 in fulfillment of the contribution agreement (RC08-1569) between Tembec and UNBC

INVENTORY OF ARBOREAL-FORAGING COMMUNITIES WITHIN WILLIAMSON’S SAPSUCKER NEST AREAS IN THE EAST KOOTENAYS

Prepared by: Robert J. Higgins Thompson Rivers University & Professor B. Staffan Lindgren University of Northern British Columbia 2

Introduction

The Williamson’s Sapsucker (WISA), Sphyrapicus thyroideus, is a cavity nesting sapsucker that

is known to occur in three geographically distinct areas in southern British Columbia, including

one population in western larch forests of the East Kootenays near the city of Cranbrook (Figure

1). This bird was assessed as endangered by the Committee on the Status of Endangered

Wildlife in Canada (COSEWIC) in 2005 and added to Schedule 1 under the Species at Risk Act

(SARA) by the federal government in 2006. This led to the commencement of recovery planning for the species.

Preliminary research (Gyug et al. unpublished) has identified (: Formicidae)

as a critical food resource linked to WISA fledging success. This is consistent with work by

Wiebe (2005) in which increased foraging on epigaeic ants by the Northern Flicker was

positively associated with fledging success. In the case of the WISA, ants are obtained from tree

boles (Crockett 1975) as the ants move up and down the trunk while foraging. Beal (1911)

described the WISA as being more dependent upon ants during the breeding season than any

other North American woodpecker.

Ants of the genus Camponotus (carpenter ants) were identified as comprising the majority of the

ant diet of the WISA (Crockett 1975), although Gyug et al. (unpublished) has also found some

species within the genus , in particular Formica aserva, that may also be a frequent food source. Both Camponotus species ants and Formica aserva are known to be dependent, in turn,

upon coarse woody debris (CWD) as a nesting resource (Hansen and Klotz 2005, Higgins and

Lindgren 2005). Horn and Hanula (2008) reported that the short-term removal of CWD from

experimental plots reduced the overall availability of to bole-foraging birds. This 3

supports the findings of Gyug et al. (unpublished) who found that WISA fledgling success correlated with ant availability, which in turn, correlated with CWD volumes.

The main objective of this project was to inventory the arboreal foraging ant communities at

WISA nests sites of varying nest productivity in order to determine the relative availability of

CWD-associated and other ant species to the WISA in the East Kootenays. This project

inventory will contribute toward a more comprehensive examination of the degree of dietary

dependence of the WISA upon CWD-associated ants in southern British Columbia (Meggs et al.

2007). The specific objectives of this project were to:

1. Compile an inventory of ant species/morphotypes available to WISA on the trunks of live

trees;

2. Quantify the diversity and abundance of ant species/morphotypes available to WISA;

3. Categorise the species/morphotype list by known or assumed habitat association (e.g.

CWD, soil or rock-associated ants)

Methods

Site inventory data relating to coarse woody debris volumes, live tree densities, and fledgling

success were previously collected by Gyug et al. (unpublished.) using Resource Information

Standards Committee (RISC) guidelines as outlined in the FIA Activity Standards Document for

Williamson Sapsucker Nests and Territories (MoE 2006). Canopy cover was measured as per

RISC guidelines during trap installation. Sampling for ants followed, where possible, the

Inventory Methods for Terrestrial Arthropods (MELP 1998), although the requirement for

sampling upon tree boles necessitated a unique sampling design. 4

Sampling methodology followed Meggs et al. (2007). In this study we used trunk traps (Figure

2), to intercept ants moving along the surface of tree boles. Sampling occurred within a 16 ha

area centred upon the nest tree. The size of the sampling area was chosen to correspond to the

known minimum foraging area for the WISA given that adjacent nests are normally no closer

than 450 m to each other (Guyg et al. unpublished). Centred on each of the seven identified

WISA nests (Appendix 1), twelve trunk traps were positioned every 30 degrees at a random

distance between 10 and 225 m. Traps were not placed closer than 10 m to the nest tree to avoid

oversampling the area immediately adjacent to the nest. Each trap was placed on a tree bole just

above a height of 2.5 m to avoid damage from cattle and held in place by two 13 mm wood

screws. Traps were put in place in mid-June 2008, and removed approximately two weeks later.

This trapping period was selected to coincide with active foraging by the WISA for ants during

the WISA chick-rearing season,..

Samples collected following the removal of the traps were cleaned of debris and the ants sorted,

identified, and then stored in 95% alcohol. As carpenter ants (genus Camponotus) have been

reported to be of significance in the diet of the WISA (Gyug et al, unpublished) these ants were

identified to species where possible (Table 3). Ants of the genus Formica were identified to the

level of species complexes except where anatomical features made identification to species

readily possible (e.g., Formica aserva). Other ants were identified to the level of genus.

Taxonomy followed Bolton (2005).

The number of individual ants of each species or morphospecies (i.e., taxa) in a trap was

counted, however presence/absence was used for analysis. This was necessary because the

unequal distribution of ants within their foraging area generally results in unreliable estimates of

abundance. Traps placed on trails used by ants to access resources will accumulate large 5

numbers of ants while a trap in close proximity may collect few making abundance based analysis of individual traps of little value. The relative abundance of ant taxa at each site (i.e.,

WISA nest area) was determined by calculating the frequency of occurrence of each taxa from individual trap data pooled by site. Individual trap data were then pooled across all sites to determine the frequency of occurrence of each taxa for WISA nest areas in the East Kootenay region.

Results include all species of ants collected, not just those suspected of being used as a food source by the WISA. 6

Results and Discussion

Background data are available for each WISA nest site relating to fledgling success, productivity class, coarse woody debris volumes, live tree density, and canopy cover (Table 1).

Table 1. Fledgling success, productivity class, coarse woody debris (CWD) volumes, live tree density and canopy cover data for seven WISA nesting sites in the East Kootenays. Site code Fledged Fledged Fledged Product- CWD Merchantable Canopy ivity Young Young Young volume tree (>17.5cm) Cover Class density 2006 2007a* 2008b (m3/ha)c (%)d (H=high; (trees/ha)c L=low)*** WNE003 Successful 5 Unoccupied H 15.7 129.8 6.3

WNE010 Unoccupied 4 Unoccupied H 9.5 176.0 13.5

WNE011 Unknown 5 Reoccupied H 0.6 98.6 13.8 WNE012 Unknown 5 Unoccupied H 9.4 97.1 12.9

WNE013 Unknown 4(3) Unoccupied H** 33.1 64.2 13 but nest within 100m occupied WNE014 Unknown 4(2) Unoccupied H** 11.4 86.7 12.6 but nest within 100m fledged 3 young WNE015 Unknown 3 Unoccupied L 21.4 100.7 7 a Ohanjanian et al. (2007) b Ohanjanian et al. (2008) c Gyug et al. (unpublished) d Tembec – Cranbrook Division *Two concerns relate to these data (Ohanjanian pers. comm.). First, nest observations taken on June 18, 2007 found only the young in WNE010 andWNE011 were old enough on the day of observation to meet FIA standards of successful fledgling (i.e., 22 days old). Second, nest observations of WNE013 and WNE014 induced early fledging and anthropogenic mortality of some young. Number in brackets represent successfully fledged after anthropogenic-induced mortality. 7

**Each of these nests were originally designated as low productivity in this project based on the post-anthropogenic fledged number. ***Nests in which 4 or more young successfully fledged were considered high productivity while nests with less than 4 were considered low productivity (Gyug et al. unpublished).

A few trunk traps were not recovered (Table 2). This may have been due to errors associated with GPS accuracy when recording trap locations, errors in GPS accuracy when relocating traps, or disturbance by human or activity.

Table 2. The number of trunk traps set and relocated at seven WISA nest areas in the East Kootenays. Site Code Number of traps set Number of traps recovered Reason for failure to recover trap WNE003 12 10 Unable to relocate 2 traps WNE010 12 11 Unable to relocate 1 trap

WNE011 12 12

WNE012 12 12

WNE013 12 10 Unable to relocate 2 traps

WNE014 12 11 Unable to relocate 1 trap

WNE015 12 12

In total, 13 species or morphospecies of ants were captured in trunk traps at the East Kootenay sites (Table 3). Based on this initial determination, we anticipate that a full species determination would result in the identification of 20-30 species. Of the 13 taxa identified, five were carpenter ants in the genus Camponotus. Several of these species require large diameter stumps or coarse woody debris for nesting (Table 4), as their nests can become very large with up to 50,000 workers (Hölldobler and Wilson 1990). Preliminary examination of WISA fecal sacs by Gyug et al. (unpublished), found carpenter ants to be the most common ant present, although they also 8

tentatively identified Formica aserva as a frequent prey item. While this latter species can nest

broadly in differing habitats (Table 4), it is most commonly located nesting within CWD,

especially in forests.

Table 3. Ant species (Hymenoptera: Formicidae) collected from tree trunk intercept traps (Figure 2) at seven Williamson’s Sapsucker (Sphyrapicus thyroideus) nest areas in the East Kootenay region of British Columbia, Canada. follows Bolton (1995) except where more recent revisions are available. FAMILY FORMICIDAE Sub-family Dolichoderinae Tapinoma sessile (Say) Sub-family Camponotus (Camponotus) herculeanus (Linnaeus) Camponotus (Camponotus) laevigatus (Smith, F.) Camponotus (Camponotus) modoc Wheeler, W.M. Camponotus (Tanaemyrmex) semitestaceous Snelling* Camponotus (Tanaemyrmex) vicinus Mayr Lasius spp. Formica fusca species complex Formica spp. Formica neogagates species complex Formica spp. Formica rufa species complex Formica spp. Formica sanguinea species complex Formica aserva Forel Sub-family Myrmicinae Leptothorax spp. Myrmica spp. *New record for British Columbia 9

Table 4. Ant (Hymenoptera: Formicidae) species sizes and known or assumed nesting sites for each species or species complex of ants collected from trunk traps in the East Kootenay region of British Columbia. Ant species sizes (anterior of head to posterior of the gaster) are approximations derived from experience of the authors. Nesting information derived from Naumann et al. (1999), and personal observations of the authors.

Nesting habitat

Ant taxon Ant length (mm) CWD Rock Soil Thatched nest

Camponotus herculeanus Majors ≥ 8 YES NO NO NO

Camponotus laevigatus Majors ≥ 8 YES NO NO NO

Camponotus modoc Majors ≥ 8 YES NO NO NO

Camponotus semitestaceous Majors ≥ 8 NO YES YES NO

Camponotus vicinus Majors ≥ 8 YES YES YES NO

Formica aserva ≥7 YES YES YES YES1

Formica rufa complex ≥7 NO NO NO YES

Formica fusca complex 4-6 YES YES YES NO

Formica neogagates complex 4-6 NO YES YES NO

Tapinoma sessile 2-4 YES YES YES NO

Lasius spp. 3-5 YES YES YES NO

Myrmica spp. 3-5 YES YES YES NO

Leptothorax spp. 2-3 YES YES YES NO

1. Thatching may occur but it is normally surrounding a stump or along the sides of downed woody debris

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Collectively, Camponotus species were relatively abundant in WISA nest areas in the East

Kootenay region, with Camponotus vicinus in particular occurring at high frequencies at two nest

sites (Table 5). Formica fusca group ants were also commonly trapped (Table 5), and based on

preliminary assessment, most of these appeared to be Formica neorufibarbis, a species generally

found nesting in woody debris. Formica fusca group species are also important as a slave-

species for Formica aserva, especially during colony founding (Higgins and Lindgren, in prep).

While the relative abundance of Formica aserva which also makes use of large pieces of woody debris (Table 4), was not high within the East Kootenay region, the large size of these ants

(Table 4) and their tentative identification in the preliminary fecal sac analysis (Gyug et al.

2006), suggest that attention should also be given to this species and its ecological requirements. 11

Table 5. The relative abundance of ants (Hymenoptera: Formicidae) (expressed as a percent of traps with that taxon trapped) captured by trunk traps at each of seven WISA nest sites sampled in the East Kootenay region of British Columbia.

WISA Nest Site

Ant taxon WNE003 WNE010 WNE012 WNE014 WNE011 WNE013 WNE015 Pooled sites Camponotus 26.7 35.3 47.6 11.1 37.5 23.1 16.8 28.3 spp. pooled Camponotus 20 0 0 11.1 4.2 7.7 5.6 6.7 herculeanus Camponotus 0 0 19 0 12.5 0 5.6 5.9 laevigatus Camponotus 6.7 0 4.8 0 0 7.7 0 2.2 modoc Camponotus 0 0 0 0 12.5 0 0 2.2 semitestaceous Camponotus 0 35.3 23.8 0 8.3 7.7 0 10.4 vicinus Formica 0 5.9 4.8 11.1 4.2 0 5.6 5.2 aserva Formica rufa 0 0 14.3 0 4.2 15.4 0 4.4 complex Formica fusca 33.3 41.2 23.8 11.1 33.3 38.5 33.3 28.9 complex Formica 0 0 0 0 4.2 0 5.6 1.5 neogagates Tapinoma 6.7 0 4.8 11.1 0 0 5.6 4.4 sessile Lasius spp. 6.7 0 0 14.8 12.5 0 11.1 7.4

Myrmica spp. 13.3 17.6 0 18.5 0 15.4 11.1 10.4 Leptothorax 13.3 0 4.8 22.2 4.2 7.7 16.7 10.4 spp.

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While relatively abundant compared to larger taxa, and frequently caught at in some nest areas

(Table 5), ants of the genera Tapinoma, Leptothorax, Lasius and Myrmica are unlikely to be a significant food source for the WISA because of their small size (typically 2-5mm). The examination of WISA fecal sacs, planned as a component of a broader study on the WISA diet to further develop the preliminary work of Gyug et al. (unpublished), should clarify the role of

these smaller ants in the diet of the WISA (Meggs et al. 2007).

Acknowledgements

This report is a component of a larger Forest Investment Account – Forest Science Program

project (Dietary dependence of Williamson’s Sapsucker on coarse woody debris-associated ants:

Y091172), with principal investigators Jeff Meggs (Streamline Environmental Consulting Ltd.)

and Robert Higgins (TRU). The advice and assistance of Les Gyug (Okanagan Wildlife

Consulting (OWC)), Penny Ohanjanian (P. Ohanjanian Consulting Biologist (POCB)), Melissa

Todd (Ministry of Forests & Range), Kevin Fort (Canadian Wildlife Service) and Kari Stuart-

Smith (Tembec Industries Inc.: Cranbrook Division) in support of this project is greatly

appreciated. This project was dependent upon the field assistance of James Jones (UNBC),

Shirley Hansen (POCB), Peter Beare (POCB), Peter Davidson (POCB), Melissa Baker

(Tembec), and Krystal Dixon (Tembec). The majority of the ant samples were processed and

identified by James Jones (UNBC).

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B.C. U% Golden Revelstoke U%

Lillooet East U% U% Kamloops Kootenay # Vernon U% Lytton U% Mer##ritt #U% Alta. # ### # #### ####### Cranbrook #### Kelowna U% U% ### #### # #### ## # # U% Penticton # Nelson # U% ### ####### #### U%# ##### U% Princ#eton # Hope ##### ### ## ## ### ### # # ## U% ######## Grand Forks N Idaho Mont. 50 0 50 KmKilometers Wash.

Figure 1. The range of Williamson's Sapsucker in the southern interior of British Columbia, shown as minimum convex polygons around all known breeding locations in BC. Also shown are the location of WISA nests for which habitat data was collected in 2006 and 2007 (from Gyug et al. (unpublished). 14

Figure 2. The trunk trap designed by the authors and used to sample arboreal foraging ants in WISA nest areas in the East Kootenays consisted of a plastic pop bottle cut to the shape of a funnel and inverted into the lid of a standard sampling container. The traps are screwed to the tree trunk and the container is partially filled with a killing/preservative agent, usually a mix of 25-50 % propylene glycol and 50-75 % water (Photo credit: R. Higgins).

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Bolton B, Alpert G, Ward PS, Naskrecki P. 2005. [CD-ROM] Bolton’s Catalogue of the Ants of the World. Harvard University Press.

Crockett AB. 1975. [PhD dissertation] Ecology and behaviour of the Williamson Sapsucker in Colorado. University of Colorado, CO. 126p.

Gyug L, Wilson S, Steeger C, Ohanjanian I. Unpub. Bayesian belief network modeling of foraging resources and nest productivity for Williamson’s Sapsucker (Sphyrapicus thyroideus) in British Columbia. Hansen LD, Klotz JH. 2005. Carpenter ants of the United States and Canada. Comstock Publishing Associates. Ithaca and London. 204p. Higgins R, Lindgren BS. 2006. The fine scale physical attributes of coarse woody debris and effects of surrounding stand structure on its utilization by ants (Hymenoptera: Formicidae) in British Columbia, Canada. Biodiversity and Dead Wood: Proceedings of a symposium for the 22nd International Congress of Entomology. 2004. Southern Research Station, U.S. Department of Agriculture Forest Service. 67 p. Hölldobler B, Wilson EO. 1990. The ants. Cambridge, Massachusetts: The Belknap Press of Harvard University Press. 732 p. Horn S, Hanula JL. 2008. Relationship of coarse woody debris to availability for Red- Cockaded Woodpeckers and other bark-foraging birds on loblolly pine boles. J. Entomol. Sci. 43(2): 153-169. Naumann K, Preston WB, Ayre GL. 1999. An annotated checklist of the ants (Hymenoptera: Formicidae) of British Columbia. Journal of the Entomological Society of British Columbia 96:29-68. Meggs J, Higgins RJ, Todd M, Lindgren BS, Gyug L, Fort K. 2007. [Research Proposal] Dietary dependence of Williamson’s sapsucker on coarse woody debris-associated ants. British Columbia Forest Science Program 2008/2009. Proposal Y091172. MELP. 1998. Inventory Methods for Terrestrial Arthropods Version 2.0. Standards for Components of British Columbia’s Biodiversity No. 40. Prepared by the BC Ministry of Environment, Lands and Parks for the Resource Inventory Committee. 16

MoE. 2006. Information Gathering and Management Component, Resource Inventories Activity Area, Wildlife and Wildlife Habitat Activities, specifically Vegetation Measurements at Williamson’s Sapsucker Nests and Territories. FIA Activity Standards Document. BC Ministry of Environment. Ohanjanian P, Davidson P, Hansen S, Conroy C. 2007. Williamson’s Sapsucker in the east Kootenay region: Results of 2007 inventory. Report for Tembec, British Columbia Forest Investment Account and British Columbia Ministry of the Environment. Ohanjanian P, Davidson P, Hansen S, Beare J. 2008. Williamson’s Sapsucker in the east Kootenay region: Results of 2008 inventory. Report for Tembec, British Columbia Forest Investment Account and British Columbia Ministry of the Environment. Wiebe KL. 2005. Asymmetric costs favour female desertion in the facultative polyandrous Northen Flicker (Colaptes auratus): a removal experiment. Behavioural Ecology and Sociobiology. 57: 429-437.