Double-crested cormorants (Phalacrocorax auritus) of Leech Lake, Minnesota: Temporal variation of diets and assessment of differential prey selection in adults

Peter J. Hundt, Andrew M. Simons, Donald L. Pereira

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

In 1998, after 160 y without documented nesting, Double-crested Cormorants (Phalacrocorax auritus) recolonized Leech Lake, Minnesota. Competition for nesting space with the state threatened Common Tern (Sterna hirundo), and concern regarding potential walleye (Sander vitreus) and yellow perch (Perca flavescens) population declines prompted culling of cormorants and research into their diet. Stomach contents of adult and subadult cormorants were collected in 2004, 2005, and 2006 (186, 356 and 348, respectively) and from cormorant chick regurgitants in 2005 and 2006 (151 and 114, respectively). Perca flavescens (>70% composition and biomass) and shiner species (Notropis sp.) (>4% composition and biomass) were the main components of subadult and adult cormorant diets in 2004 and 2005 and the diet of chicks in 2005. However in 2006, whitefish species (Coregonus sp.) was the majority of percent biomass consumed by subadults and adults (43.4%) and a large proportion of percent biomass consumed by chicks (17.8%). In 2006 percent biomass of Corengonus sp. was different from other years for adults and subadults (P < 0.001) and chicks (P < 0.01) and may have been a product of a warming event die-off in late summer. All eight of the select common prey species varied (P < 0.01) in percent biomass between at least one of the ten delineated periods within 2004, 2005, or 2006. Differential prey selection by adults for self-feeding and provisioning for chicks was detected in Coregonus sp. (P < 0.01). While the diet of Leech Lake cormorants mainly consists of small abundant fish (P. flavescens and Notropis sp.), cormorant diet can vary within and among years. This study represents the first description of the diet of cormorants from a midwestern location other than the Great Lakes and reinforces the importance of site specific diet assessment, as the particular abundant prey species differs between locations.

Original languageEnglish (US)
Pages (from-to)354-370
Number of pages17
JournalAmerican Midland Naturalist
Volume169
Issue number2
DOIs
StatePublished - Apr 1 2013

Fingerprint

Phalacrocorax auritus
leech
prey selection
Hirudinea
Phalacrocorax
temporal variation
chicks
Perca flavescens
diet
lakes
lake
biomass
Notropis
Coregonus
Sterna hirundo
culling
die-off
Sander vitreus
culling (animals)
stomach content

Cite this

@article{2b2c7f0cd5994900a85b7426093e7689,
title = "Double-crested cormorants (Phalacrocorax auritus) of Leech Lake, Minnesota: Temporal variation of diets and assessment of differential prey selection in adults",
abstract = "In 1998, after 160 y without documented nesting, Double-crested Cormorants (Phalacrocorax auritus) recolonized Leech Lake, Minnesota. Competition for nesting space with the state threatened Common Tern (Sterna hirundo), and concern regarding potential walleye (Sander vitreus) and yellow perch (Perca flavescens) population declines prompted culling of cormorants and research into their diet. Stomach contents of adult and subadult cormorants were collected in 2004, 2005, and 2006 (186, 356 and 348, respectively) and from cormorant chick regurgitants in 2005 and 2006 (151 and 114, respectively). Perca flavescens (>70{\%} composition and biomass) and shiner species (Notropis sp.) (>4{\%} composition and biomass) were the main components of subadult and adult cormorant diets in 2004 and 2005 and the diet of chicks in 2005. However in 2006, whitefish species (Coregonus sp.) was the majority of percent biomass consumed by subadults and adults (43.4{\%}) and a large proportion of percent biomass consumed by chicks (17.8{\%}). In 2006 percent biomass of Corengonus sp. was different from other years for adults and subadults (P < 0.001) and chicks (P < 0.01) and may have been a product of a warming event die-off in late summer. All eight of the select common prey species varied (P < 0.01) in percent biomass between at least one of the ten delineated periods within 2004, 2005, or 2006. Differential prey selection by adults for self-feeding and provisioning for chicks was detected in Coregonus sp. (P < 0.01). While the diet of Leech Lake cormorants mainly consists of small abundant fish (P. flavescens and Notropis sp.), cormorant diet can vary within and among years. This study represents the first description of the diet of cormorants from a midwestern location other than the Great Lakes and reinforces the importance of site specific diet assessment, as the particular abundant prey species differs between locations.",
author = "Hundt, {Peter J.} and Simons, {Andrew M.} and Pereira, {Donald L.}",
year = "2013",
month = "4",
day = "1",
doi = "10.1674/0003-0031-169.2.354",
language = "English (US)",
volume = "169",
pages = "354--370",
journal = "American Midland Naturalist",
issn = "0003-0031",
publisher = "University of Notre Dame",
number = "2",

}

TY - JOUR

T1 - Double-crested cormorants (Phalacrocorax auritus) of Leech Lake, Minnesota

T2 - Temporal variation of diets and assessment of differential prey selection in adults

AU - Hundt, Peter J.

AU - Simons, Andrew M.

AU - Pereira, Donald L.

PY - 2013/4/1

Y1 - 2013/4/1

N2 - In 1998, after 160 y without documented nesting, Double-crested Cormorants (Phalacrocorax auritus) recolonized Leech Lake, Minnesota. Competition for nesting space with the state threatened Common Tern (Sterna hirundo), and concern regarding potential walleye (Sander vitreus) and yellow perch (Perca flavescens) population declines prompted culling of cormorants and research into their diet. Stomach contents of adult and subadult cormorants were collected in 2004, 2005, and 2006 (186, 356 and 348, respectively) and from cormorant chick regurgitants in 2005 and 2006 (151 and 114, respectively). Perca flavescens (>70% composition and biomass) and shiner species (Notropis sp.) (>4% composition and biomass) were the main components of subadult and adult cormorant diets in 2004 and 2005 and the diet of chicks in 2005. However in 2006, whitefish species (Coregonus sp.) was the majority of percent biomass consumed by subadults and adults (43.4%) and a large proportion of percent biomass consumed by chicks (17.8%). In 2006 percent biomass of Corengonus sp. was different from other years for adults and subadults (P < 0.001) and chicks (P < 0.01) and may have been a product of a warming event die-off in late summer. All eight of the select common prey species varied (P < 0.01) in percent biomass between at least one of the ten delineated periods within 2004, 2005, or 2006. Differential prey selection by adults for self-feeding and provisioning for chicks was detected in Coregonus sp. (P < 0.01). While the diet of Leech Lake cormorants mainly consists of small abundant fish (P. flavescens and Notropis sp.), cormorant diet can vary within and among years. This study represents the first description of the diet of cormorants from a midwestern location other than the Great Lakes and reinforces the importance of site specific diet assessment, as the particular abundant prey species differs between locations.

AB - In 1998, after 160 y without documented nesting, Double-crested Cormorants (Phalacrocorax auritus) recolonized Leech Lake, Minnesota. Competition for nesting space with the state threatened Common Tern (Sterna hirundo), and concern regarding potential walleye (Sander vitreus) and yellow perch (Perca flavescens) population declines prompted culling of cormorants and research into their diet. Stomach contents of adult and subadult cormorants were collected in 2004, 2005, and 2006 (186, 356 and 348, respectively) and from cormorant chick regurgitants in 2005 and 2006 (151 and 114, respectively). Perca flavescens (>70% composition and biomass) and shiner species (Notropis sp.) (>4% composition and biomass) were the main components of subadult and adult cormorant diets in 2004 and 2005 and the diet of chicks in 2005. However in 2006, whitefish species (Coregonus sp.) was the majority of percent biomass consumed by subadults and adults (43.4%) and a large proportion of percent biomass consumed by chicks (17.8%). In 2006 percent biomass of Corengonus sp. was different from other years for adults and subadults (P < 0.001) and chicks (P < 0.01) and may have been a product of a warming event die-off in late summer. All eight of the select common prey species varied (P < 0.01) in percent biomass between at least one of the ten delineated periods within 2004, 2005, or 2006. Differential prey selection by adults for self-feeding and provisioning for chicks was detected in Coregonus sp. (P < 0.01). While the diet of Leech Lake cormorants mainly consists of small abundant fish (P. flavescens and Notropis sp.), cormorant diet can vary within and among years. This study represents the first description of the diet of cormorants from a midwestern location other than the Great Lakes and reinforces the importance of site specific diet assessment, as the particular abundant prey species differs between locations.

UR - http://www.scopus.com/inward/record.url?scp=84875435985&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84875435985&partnerID=8YFLogxK

U2 - 10.1674/0003-0031-169.2.354

DO - 10.1674/0003-0031-169.2.354

M3 - Article

AN - SCOPUS:84875435985

VL - 169

SP - 354

EP - 370

JO - American Midland Naturalist

JF - American Midland Naturalist

SN - 0003-0031

IS - 2

ER -