Estimating sex-specific abundance in fawning areas of a high-density Columbian black-tailed deer population using fecal DNA

Zachary Lounsberry, Tavis D. Forrester, Maryjo T. Olegario, Jennifer L. Brazeal, Heiko U. Wittmer, Benjamin Sacks

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

The recent development of fecal-genetic capture-mark-recapture (CMR) methods has increased the feasibility of estimating abundance of forest-dwelling ungulates that are difficult to survey using visual methods. Unless genetic markers differentiating sex are incorporated into such studies, however, genetic CMR approaches risk missing sex-specific differences in population trends. We developed a single-reaction genetic assay for sex and individual identification, including 10 microsatellites and an SRY marker, and applied it in the context of a post-fawning CMR study of Columbian black-tailed deer (Odocoileus hemionus columbianus) in forested habitat of coastal California during 2011 and 2012. We measured sex-specific abundance and sex ratios in high-quality summer habitats encompassing 4 distinct fawning areas. We detected a significant interaction between sex and year, indicating different trends in the abundance of males and females. We also detected a significant decline in abundance of females between years (P = 0.045), which agreed with independent telemetry-based estimates, and significant differences in female abundance among fawning areas (P = 0.020) but no significant differences in the abundance of males for either variable (F1-3,20 < 0.710, P > 0.410). When sex was not considered in the analysis, we found no significant differences in abundance between the 2 years, suggesting that differing trends between the 2 sexes obscured the female-specific patterns. We estimated average local (i.e., on the high-quality summer ranges) density (D^) for females at 41.0 (± 5.9) deer/km2 in 2011 and 29.1 (± 6.8) deer/km2 in 2012, and local density of males at 15.7 (± 3.0) deer/km2 across the 2 study years. Accordingly, sex ratios differed between years (95% CI = 3.0-4.2 F:M ratio in 2011, 2.0-2.3 F:M ratio in 2012). Incorporating sex and individual markers into a single assay provided a cost-effective means of applying CMR estimation based on fecal DNA to a high-density ungulate population in a forested ecosystem and emphasized the importance of explicitly modeling sex in abundance estimation.

Original languageEnglish (US)
Pages (from-to)39-49
Number of pages11
JournalJournal of Wildlife Management
Volume79
Issue number1
DOIs
StatePublished - Jan 1 2015

Fingerprint

Odocoileus hemionus
deer
DNA
gender
ungulate
sex ratio
ungulates
assay
abundance estimation
mark-recapture method
genetic marker
summer
habitat
telemetry
mark-recapture studies
assays
habitats
ecosystem
microsatellite repeats
cost

Keywords

  • abundance
  • black-tailed deer
  • mark-recapture
  • microsatellite
  • noninvasive DNA
  • sex ratio

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Nature and Landscape Conservation

Cite this

Estimating sex-specific abundance in fawning areas of a high-density Columbian black-tailed deer population using fecal DNA. / Lounsberry, Zachary; Forrester, Tavis D.; Olegario, Maryjo T.; Brazeal, Jennifer L.; Wittmer, Heiko U.; Sacks, Benjamin.

In: Journal of Wildlife Management, Vol. 79, No. 1, 01.01.2015, p. 39-49.

Research output: Contribution to journalArticle

Lounsberry, Zachary ; Forrester, Tavis D. ; Olegario, Maryjo T. ; Brazeal, Jennifer L. ; Wittmer, Heiko U. ; Sacks, Benjamin. / Estimating sex-specific abundance in fawning areas of a high-density Columbian black-tailed deer population using fecal DNA. In: Journal of Wildlife Management. 2015 ; Vol. 79, No. 1. pp. 39-49.
@article{6595d7e354c9405d9d48b9b99a2819d2,
title = "Estimating sex-specific abundance in fawning areas of a high-density Columbian black-tailed deer population using fecal DNA",
abstract = "The recent development of fecal-genetic capture-mark-recapture (CMR) methods has increased the feasibility of estimating abundance of forest-dwelling ungulates that are difficult to survey using visual methods. Unless genetic markers differentiating sex are incorporated into such studies, however, genetic CMR approaches risk missing sex-specific differences in population trends. We developed a single-reaction genetic assay for sex and individual identification, including 10 microsatellites and an SRY marker, and applied it in the context of a post-fawning CMR study of Columbian black-tailed deer (Odocoileus hemionus columbianus) in forested habitat of coastal California during 2011 and 2012. We measured sex-specific abundance and sex ratios in high-quality summer habitats encompassing 4 distinct fawning areas. We detected a significant interaction between sex and year, indicating different trends in the abundance of males and females. We also detected a significant decline in abundance of females between years (P = 0.045), which agreed with independent telemetry-based estimates, and significant differences in female abundance among fawning areas (P = 0.020) but no significant differences in the abundance of males for either variable (F1-3,20 < 0.710, P > 0.410). When sex was not considered in the analysis, we found no significant differences in abundance between the 2 years, suggesting that differing trends between the 2 sexes obscured the female-specific patterns. We estimated average local (i.e., on the high-quality summer ranges) density (D^) for females at 41.0 (± 5.9) deer/km2 in 2011 and 29.1 (± 6.8) deer/km2 in 2012, and local density of males at 15.7 (± 3.0) deer/km2 across the 2 study years. Accordingly, sex ratios differed between years (95{\%} CI = 3.0-4.2 F:M ratio in 2011, 2.0-2.3 F:M ratio in 2012). Incorporating sex and individual markers into a single assay provided a cost-effective means of applying CMR estimation based on fecal DNA to a high-density ungulate population in a forested ecosystem and emphasized the importance of explicitly modeling sex in abundance estimation.",
keywords = "abundance, black-tailed deer, mark-recapture, microsatellite, noninvasive DNA, sex ratio",
author = "Zachary Lounsberry and Forrester, {Tavis D.} and Olegario, {Maryjo T.} and Brazeal, {Jennifer L.} and Wittmer, {Heiko U.} and Benjamin Sacks",
year = "2015",
month = "1",
day = "1",
doi = "10.1002/jwmg.817",
language = "English (US)",
volume = "79",
pages = "39--49",
journal = "Journal of Wildlife Management",
issn = "0022-541X",
publisher = "Wiley-Blackwell",
number = "1",

}

TY - JOUR

T1 - Estimating sex-specific abundance in fawning areas of a high-density Columbian black-tailed deer population using fecal DNA

AU - Lounsberry, Zachary

AU - Forrester, Tavis D.

AU - Olegario, Maryjo T.

AU - Brazeal, Jennifer L.

AU - Wittmer, Heiko U.

AU - Sacks, Benjamin

PY - 2015/1/1

Y1 - 2015/1/1

N2 - The recent development of fecal-genetic capture-mark-recapture (CMR) methods has increased the feasibility of estimating abundance of forest-dwelling ungulates that are difficult to survey using visual methods. Unless genetic markers differentiating sex are incorporated into such studies, however, genetic CMR approaches risk missing sex-specific differences in population trends. We developed a single-reaction genetic assay for sex and individual identification, including 10 microsatellites and an SRY marker, and applied it in the context of a post-fawning CMR study of Columbian black-tailed deer (Odocoileus hemionus columbianus) in forested habitat of coastal California during 2011 and 2012. We measured sex-specific abundance and sex ratios in high-quality summer habitats encompassing 4 distinct fawning areas. We detected a significant interaction between sex and year, indicating different trends in the abundance of males and females. We also detected a significant decline in abundance of females between years (P = 0.045), which agreed with independent telemetry-based estimates, and significant differences in female abundance among fawning areas (P = 0.020) but no significant differences in the abundance of males for either variable (F1-3,20 < 0.710, P > 0.410). When sex was not considered in the analysis, we found no significant differences in abundance between the 2 years, suggesting that differing trends between the 2 sexes obscured the female-specific patterns. We estimated average local (i.e., on the high-quality summer ranges) density (D^) for females at 41.0 (± 5.9) deer/km2 in 2011 and 29.1 (± 6.8) deer/km2 in 2012, and local density of males at 15.7 (± 3.0) deer/km2 across the 2 study years. Accordingly, sex ratios differed between years (95% CI = 3.0-4.2 F:M ratio in 2011, 2.0-2.3 F:M ratio in 2012). Incorporating sex and individual markers into a single assay provided a cost-effective means of applying CMR estimation based on fecal DNA to a high-density ungulate population in a forested ecosystem and emphasized the importance of explicitly modeling sex in abundance estimation.

AB - The recent development of fecal-genetic capture-mark-recapture (CMR) methods has increased the feasibility of estimating abundance of forest-dwelling ungulates that are difficult to survey using visual methods. Unless genetic markers differentiating sex are incorporated into such studies, however, genetic CMR approaches risk missing sex-specific differences in population trends. We developed a single-reaction genetic assay for sex and individual identification, including 10 microsatellites and an SRY marker, and applied it in the context of a post-fawning CMR study of Columbian black-tailed deer (Odocoileus hemionus columbianus) in forested habitat of coastal California during 2011 and 2012. We measured sex-specific abundance and sex ratios in high-quality summer habitats encompassing 4 distinct fawning areas. We detected a significant interaction between sex and year, indicating different trends in the abundance of males and females. We also detected a significant decline in abundance of females between years (P = 0.045), which agreed with independent telemetry-based estimates, and significant differences in female abundance among fawning areas (P = 0.020) but no significant differences in the abundance of males for either variable (F1-3,20 < 0.710, P > 0.410). When sex was not considered in the analysis, we found no significant differences in abundance between the 2 years, suggesting that differing trends between the 2 sexes obscured the female-specific patterns. We estimated average local (i.e., on the high-quality summer ranges) density (D^) for females at 41.0 (± 5.9) deer/km2 in 2011 and 29.1 (± 6.8) deer/km2 in 2012, and local density of males at 15.7 (± 3.0) deer/km2 across the 2 study years. Accordingly, sex ratios differed between years (95% CI = 3.0-4.2 F:M ratio in 2011, 2.0-2.3 F:M ratio in 2012). Incorporating sex and individual markers into a single assay provided a cost-effective means of applying CMR estimation based on fecal DNA to a high-density ungulate population in a forested ecosystem and emphasized the importance of explicitly modeling sex in abundance estimation.

KW - abundance

KW - black-tailed deer

KW - mark-recapture

KW - microsatellite

KW - noninvasive DNA

KW - sex ratio

UR - http://www.scopus.com/inward/record.url?scp=84919344051&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84919344051&partnerID=8YFLogxK

U2 - 10.1002/jwmg.817

DO - 10.1002/jwmg.817

M3 - Article

AN - SCOPUS:84919344051

VL - 79

SP - 39

EP - 49

JO - Journal of Wildlife Management

JF - Journal of Wildlife Management

SN - 0022-541X

IS - 1

ER -