First records of Lasiurus cinereus and L. borealis (Chiroptera: Vespertilionidae) on Cape Breton Island, Nova Scotia, Canada

Publisher's Version/PDFIn August 2012, a Lasiurus cinereus (Hoary Bat) and 2 Lasiurus borealis (Eastern Red Bat) were netted near Donkin, Cape Breton Island, NS, Canada. Acoustic studies showed the presence of Hoary Bats on at least 3 nights and Eastern Red Bats on at least 16 nights, over a 32-night-long survey starting on 21 August 2012. These records are the first for both species on Cape Breton Island, and significantly extend the known distribution of Eastern Red Bats.</p

Carbon (δ¹³C) and Nitrogen (δ¹⁵N) Stable Isotope Signatures in Bat Fur Indicate Swarming Sites Have Catchment Areas for Bats from Different Summering Areas

<div><p>Migratory patterns of bats are not well understood and traditional methods to study this, like capture-mark-recapture, may not provide enough detail unless there are many records. Stable isotope profiles of many animal species have been used to make inferences about migration. Each year <i>Myotis lucifugus</i> and <i>M</i>. <i>septentrionalis</i> migrate from summering roosts to swarming caves and mines in the fall, but the pattern of movement between them is not well understood. In this study, fur δ¹³C and δ¹⁵N values of 305 <i>M</i>. <i>lucifugus</i> and 200 <i>M</i>. <i>septentrionalis</i> were analyzed to make inferences about migration patterns between summering areas and swarming sites in Nova Scotia, Canada. We expected that there would be greater variability in δ¹³C and δ¹⁵N among individuals at swarming sites because it was believed that these sites are used by individuals originating from many summering areas. There was extensive overlap in the standard ellipse area, corrected for small sample sizes (SEA_c), of bats at swarming sites and much less overlap in SEA_c among groups sampled at summering areas. Meaningful inference could not be made on <i>M</i>. <i>septentrionalis</i> because their low variation in SEAc may have been the result of sampling only 3 summering areas. However, for <i>M</i>. <i>lucifugus</i>, swarming sites had larger SEA_c than summering areas and predictive discriminant analysis assigned swarming bats to multiple summering areas, supporting the contention that swarming bats are mixed aggregations of bats from several summering areas. Together, these data support the contention that swarming sites have catchment areas for bats from multiple summering areas and it is likely that the catchment areas for swarming sites overlap. These data suggest that δ¹³C and δ¹⁵N profiling of bat fur offer some potential to make inferences about regional migration in bats.</p></div

Population level stable isotope metrics derived from <i>δ</i>¹³C and <i>δ</i>¹⁵N of fur samples of <i>M</i>. <i>lucifugus and M</i>. <i>septentrionalis</i> at summering areas and swarming sites in Nova Scotia.

<p>* Number of males sampled</p><p>** Collected over number of sampling days</p><p>*** Collected over number of sampling years</p><p>Population level stable isotope metrics derived from <i>δ</i>¹³C and <i>δ</i>¹⁵N of fur samples of <i>M</i>. <i>lucifugus and M</i>. <i>septentrionalis</i> at summering areas and swarming sites in Nova Scotia.</p

Number of <i>M</i>. <i>lucifugus</i> from swarming sites assigned to summering areas with predictive discriminant analysis.

<p>Number of <i>M</i>. <i>lucifugus</i> from swarming sites assigned to summering areas with predictive discriminant analysis.</p

Number of <i>M</i>. <i>septentrionalis</i> from swarming sites assigned to summering areas with predictive discriminant analysis.

<p>Number of <i>M</i>. <i>septentrionalis</i> from swarming sites assigned to summering areas with predictive discriminant analysis.</p

Classification matrix of <i>M</i>. <i>lucifugus</i> correctly assigned to their swarming capture sites based on <i>δ</i>¹³C and <i>δ</i>¹⁵N isotopic signatures.

<p>Classification matrix of <i>M</i>. <i>lucifugus</i> correctly assigned to their swarming capture sites based on <i>δ</i>¹³C and <i>δ</i>¹⁵N isotopic signatures.</p

Classification matrix of <i>M</i>. <i>lucifugus</i> correctly assigned to their known summering area based on <i>δ</i>¹³C and <i>δ</i>¹⁵N isotopic signatures.

<p>Classification matrix of <i>M</i>. <i>lucifugus</i> correctly assigned to their known summering area based on <i>δ</i>¹³C and <i>δ</i>¹⁵N isotopic signatures.</p

Scatter plots of <i>δ</i>¹³C ‰ and <i>δ</i>¹⁵N ‰ values of <i>M</i>. <i>lucifugus</i> (a: summering) (b: swarming) and <i>M</i>. <i>septentrionalis</i> (c: summering) (d: swarming) fur samples in Nova Scotia where ovals enclose the small sample size standard ellipse area (SEA_c; 40%).

<p>Scatter plots of <i>δ</i>¹³C ‰ and <i>δ</i>¹⁵N ‰ values of <i>M</i>. <i>lucifugus</i> (a: summering) (b: swarming) and <i>M</i>. <i>septentrionalis</i> (c: summering) (d: swarming) fur samples in Nova Scotia where ovals enclose the small sample size standard ellipse area (SEA_c; 40%).</p

Classification matrix of <i>M</i>. <i>septentrionalis</i> correctly assigned to their known summering area based on <i>δ</i>¹³C and <i>δ</i>¹⁵N isotopic signatures.

<p>Classification matrix of <i>M</i>. <i>septentrionalis</i> correctly assigned to their known summering area based on <i>δ</i>¹³C and <i>δ</i>¹⁵N isotopic signatures.</p

Sampling sites in Nova Scotia; circles indicate summering areas and triangles indicate swarming sites.

<p>Sampling sites in Nova Scotia; circles indicate summering areas and triangles indicate swarming sites.</p