OBSERVATION OF ABUNDANT NORTHERN LEOPARD FROGS AT WARGATIE LAKE, MANITOBA

Cary Hamel, Nature Conservancy of Atlas observers have reported Canada, Manitoba Region, 200-611 densities of frogs as high as 100 Corydon Ave., Winnipeg, MB R3L 0P3 individuals per 100 m2.6'7 Several [email protected] (up to five to 10 in places) northern Melissa Grantham, Nature Conservancy leopard frogs per metre of shoreline of Canada, Manitoba Region, 200-611 (considered "immense numbers") Photo credit: Annie McLec Corydon Ave., Winnipeg, MB R3L 0P3 were reported at the Pinawa sewage [email protected] the season prior to surveys).10 The lagoons in July 1990, which were property lies adjacent to perennial Conservation Status similar to observations at a Weyburn, grass pasture, hayland, wetlands, & Local Abundance Saskatchewan golf course in July and Wargatie Lake. Annual cropland The northern leopard frog 2003.7-9 occurs within 800 m of the property (.Lithobates pipiens) is a Species and is characteristic of regional land of Special Concern in the prairie Study Area & Methods use. Wargatie Lake is 160 ha large provinces.1 These frogs reguire three Surveys occurred on a 65 ha and 12 m deep.11 habitat types to complete their parcel that is a component of the While conducting vegetation life cycle: terrestrial (uplands and Nature Conservancy of Canada's surveys on September 8, 2011, native prairie) for summer foraging, Riding Mountain House conservation Nature Conservancy of Canada staff wetlands for reproduction, and project near Keeseekoowenin, south (Cary Hamel, Julie Pelc, and Levi permanent water bodies that do of Riding Mountain National Park, Newediuk) noted what appeared not freeze solid for overwintering.1'3 Manitoba (Fig. 1). The property is to be an exceptional abundance of Connectivity and close proximity characterized by Loamy lacustrine presumed young-of-the-year norther among those habitats is especially and Loamy till (well drained, slope leopard frogs. After investigating important, due to the frogs' limited 5-9%, agricultural capability 3-4) several portions of the property, the dispersal distance.2 soils and supports several pothole surveyors determined that abundanc The species was once common wetlands interspersed with annual appeared to be generally ubiguitous. enough to be commercially cropland (wheat was grown in In an attempt to guantify abundance harvested.1'4 Northern leopard frogs were particularly abundant in the southern marshes of Lake Winnipeg and Lake Manitoba, and were noted as being the most abundant frog in the Delta Marsh region in 1961,2'5 In the 1970s, however, the species started dying off from an apparent illness; large numbers of dead frogs were observed, and they seemed to disappear from major population centres.1'4-6 The species started to recover in the 1990s, with local populations having recovered significantly since then.1 Northern leopard frogs are currently considered "apparently secure" in Manitoba.3 Few guantified reports of leopard frog abundance in Manitoba are

available.1'2 Reports from some j( ★ Project Location jf 1 1 I Riding Mountain National Park \ observers suggest that they can be Figure 1: Map of the survey area, part of the Nature Conservancy of Canada's Riding Mountain Hoil locally abundant. Manitoba Herps conservation project near Keeseekoowenin, south of Riding Mountain National Park, ManitotR

12 BLUE JAY SUMMER 2016 VOLUME 74.2 ax transects were established through Table 1. Northern leopard frogs observed along six transects at the jpland areas of the property, running Nature Conservancy of Canada's Riding Mountain House conservation oughly perpendicular to Wargatie project in September 2011. .ake. Surveyors attempted to make TRANSECT I TRANSECT # NORTHERN LEOPARD # NORTHERN ransects as straight as possible and 1 LENGTH (M) FROGS OBSERVED LEOPARD FROGS/M2 oughly 100 m in length; however, 1 | 111 85 0.383 2 119 89 0.374 ictual transect length varied from 111 1 o 145 m. The beginning and end of 3 145 71 0.245 'ach transect was noted using a GPS. 4 130 69 0.265 ■■■■■■■■■■■■■■■■■■■■■■■■■■■I he flushing distance of frogs was 5 i 145 |! 45 0.155 letermined to be approximately 1 m. 6 130 83 0.319 iurveyors noted the number of frogs >bserved while walking transects. Post survey (October 2011), 5. Tamsitt JR (1961) Notes on the herpetofauna of the Delta Marsh of Lake Manitoba, Veather conditions were sunny and portions of the annual cropland on Canada. The Canadian-Field Naturalist the surveyed property were restored. ipproximately 21 degrees Celsius. 75:149-151. Ten pothole wetlands ranging in 6. Nature North (2015a) Amphibians of Results size from 0.09 to 1.10 ha in size Manitoba: Leopard Frog. Available from and encompassing 3.8 ha in total Four hundred and forty-two frogs www.naturenorth.com/1 np/Species/ vere observed along 780 m travelled were recreated. A post-restoration amphibian/1 Ffrle.html. (Accessed: April 22, Table 1). Based on a 1 m flushing examination of northern leopard frog 2015). abundance represents an interesting listance, transects were considered 7. Nature North (2015b) Manitoba Herps Atlas o be 2 m wide belts. The average research opportunity. Interactive Database. Available from www. lensity of surveyed frogs was 0.29 naturenorth.com/F1erps/MHA_Data.html (Accessed: April 22, 2015). rogs/m2, or 2,900 frogs per ha. Acknowledgements Julie Pelc and Levi Newediuk provided field 8. Taylor P (2005) Calling Periods for frogs assistance. Jean Rosset and Jordan Becker )iscussion and toads near Pinawa, Manitoba, with provided site information. Funding for NCC's an update on Mink Frog and Green Frog While our sample size was very conservation work at Wargatie Lake was distribution. Blue Jay 64(1 ):44-55. mall, the limited number of reported supported by the Government of Canada's 9. Bailey M (2004) Northern leopard frogs in a stimates of northern leopard frog Natural Areas Conservation Program, the U.S. Fish and Wildlife Service, and the Province of golf course water hazard. Blue Jay 62(1 ):43- bundance in Manitoba makes Manitoba. 45. lese observations noteworthy. Our 10. Western Land Resource Group - Agriculture ibservations appear similar to the 1. COSEWIC (2009) COSEWIC assessment and update status report on the Northern and Agri-Food Canada (2002) Rural immense' numbers reported by Taylor Leopard Frog Rana pipiens, Rocky Mountain Municipality of Park - Soil. Soils and Terrain and references therein).8 The authors Population, Western Boreal/Prairie Population 98-10. Winnipeg. acognize that survivorship between and Eastern populations, In Canada. 11. Manitoba Conservation. Wargatie Lake Committee on the Status of Endangered fe stages varies (see Kinney 2011 for Manitoba [Map], One Thousand Metre Wildlife in Canada. Ottawa. Vii + 69 pp. aview) and it is unknown how many Universal Transverse Mercator Grid. Canada (www.sararegistry.gc.ca/status/status_e.cfm). 'ogs survived to overwinter.12 Frog Map Sales, 2006. 2. Environment Canada (2013) Management bundance was notably higher at the 12. Kinney VC (2011) Adult survivorship and Plan for the Northern Leopard Frog urvey location earlier in the season juvenile recruitment in populations of (,Lithobates pipiens), Western Boreal/Prairie Crawfish Frogs (Lithobates areolatus), with _evi Newediuk, pers. comm.). Populations, in Canada. Species at Risk additional consideration of the population Pope et al. (2000) summarize Act Management Plan Series. Environment sizes of associated pond breeding species. Canada, Ottawa, iii + 28 pp. ie landscape scale considerations MSc Thesis. Indiana State University, Terre aguired to support a metapopulation 3. NatureServe (2015) NatureServe Explorer: An Haute, Indiana. >f northern leopard frogs, and their online encyclopedia of life [web application]. 13. Pope SE, Fahrig L, and Gray Merriam H Version 7.1. NatureServe, Arlington, Virginia. asults suggest that full landscape (2000) Landscape complementation and Available http://explorer.natureserve.org. tructure, including breeding habitat metapopulation effects on leopard frog (Accessed: April 23, 2015). s well as complementary habitat, populations. Ecology 81 (9):2498-2508. ^ ; linked to frog abundance.13 The 4. Koonz W (1992) Amphibians in Manitoba. In Bishop CA, Pettit KE (eds) Declines in djacency of relatively deep Wargatie Canadian Amphibian Populations: Designing ake as overwintering habitat and national monitoring strategy. Canadian lay contribute to the observed Wildlife Service, Occasional Paper No. 76:19- bundances. 20. SUMMER 2016 VOLUME 74.2 BLUE JAY 13