The interactive effects of food and predators on reproduction and overwinter survival of arctic ground squirrels
1. We examined the effects of food and predators on population limitation in the arctic ground squirrel (Spermophilus parryii plesius Richardson) in the boreal forest of the south-western Yukon. We focused on ground squirrel reproduction and overwinter survival. 2. Squirrel populations were monitore...
Main Authors: | , , , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
British Ecological Society
2000
|
Subjects: | |
Online Access: | http://hdl.handle.net/1807/355 |
id |
ftunivtoronto:oai:localhost:1807/355 |
---|---|
record_format |
openpolar |
spelling |
ftunivtoronto:oai:localhost:1807/355 2023-05-15T14:31:30+02:00 The interactive effects of food and predators on reproduction and overwinter survival of arctic ground squirrels Karels, Tim J. Byrom, Andrea E. Boonstra, Rudy Krebs, Charles J. 2000 297149 bytes application/pdf http://hdl.handle.net/1807/355 en eng British Ecological Society Journal of Animal Ecology (2000) 69, 235-247 http://hdl.handle.net/1807/355 overwinter survival population limitation reproduction Spermophilus parryii sublethal effects of predators Article 2000 ftunivtoronto 2020-06-17T11:06:21Z 1. We examined the effects of food and predators on population limitation in the arctic ground squirrel (Spermophilus parryii plesius Richardson) in the boreal forest of the south-western Yukon. We focused on ground squirrel reproduction and overwinter survival. 2. Squirrel populations were monitored by live-trapping and radio-telemetry from 1993 to the spring of 1996 on four control and four experimental areas (one preda- tor exclosure treatment, two food addition treatments, and one predator exclosure plus food addition treatment). 3. Predator exclusion increased body condition, percentage lactating, percentage weaning litters, litter size, and doubled population density relative to controls, but had no effect on juvenile growth rate, overwinter survival, or juvenile emergence date. 4. Food addition advanced juvenile emergence date and increased adult body con- dition, percentage lactating, percentage weaning litters, litter size, population den- sity relative to controls (4-7 fold), but had no effect on juvenile growth rate or overwinter survival. 5. Predator exclusion combined with food addition increased adult body condition, percentage lactating, percentage weaning litters, and population density relative to controls (19-fold). 6. We conclude that arctic ground squirrels in the boreal forest are limited by an interaction between food and predation, acting primarily through changes in repro- duction, and that their impact on density was multiplicative. Article in Journal/Newspaper Arctic ground squirrel Arctic Yukon University of Toronto: Research Repository T-Space Arctic Yukon |
institution |
Open Polar |
collection |
University of Toronto: Research Repository T-Space |
op_collection_id |
ftunivtoronto |
language |
English |
topic |
overwinter survival population limitation reproduction Spermophilus parryii sublethal effects of predators |
spellingShingle |
overwinter survival population limitation reproduction Spermophilus parryii sublethal effects of predators Karels, Tim J. Byrom, Andrea E. Boonstra, Rudy Krebs, Charles J. The interactive effects of food and predators on reproduction and overwinter survival of arctic ground squirrels |
topic_facet |
overwinter survival population limitation reproduction Spermophilus parryii sublethal effects of predators |
description |
1. We examined the effects of food and predators on population limitation in the arctic ground squirrel (Spermophilus parryii plesius Richardson) in the boreal forest of the south-western Yukon. We focused on ground squirrel reproduction and overwinter survival. 2. Squirrel populations were monitored by live-trapping and radio-telemetry from 1993 to the spring of 1996 on four control and four experimental areas (one preda- tor exclosure treatment, two food addition treatments, and one predator exclosure plus food addition treatment). 3. Predator exclusion increased body condition, percentage lactating, percentage weaning litters, litter size, and doubled population density relative to controls, but had no effect on juvenile growth rate, overwinter survival, or juvenile emergence date. 4. Food addition advanced juvenile emergence date and increased adult body con- dition, percentage lactating, percentage weaning litters, litter size, population den- sity relative to controls (4-7 fold), but had no effect on juvenile growth rate or overwinter survival. 5. Predator exclusion combined with food addition increased adult body condition, percentage lactating, percentage weaning litters, and population density relative to controls (19-fold). 6. We conclude that arctic ground squirrels in the boreal forest are limited by an interaction between food and predation, acting primarily through changes in repro- duction, and that their impact on density was multiplicative. |
format |
Article in Journal/Newspaper |
author |
Karels, Tim J. Byrom, Andrea E. Boonstra, Rudy Krebs, Charles J. |
author_facet |
Karels, Tim J. Byrom, Andrea E. Boonstra, Rudy Krebs, Charles J. |
author_sort |
Karels, Tim J. |
title |
The interactive effects of food and predators on reproduction and overwinter survival of arctic ground squirrels |
title_short |
The interactive effects of food and predators on reproduction and overwinter survival of arctic ground squirrels |
title_full |
The interactive effects of food and predators on reproduction and overwinter survival of arctic ground squirrels |
title_fullStr |
The interactive effects of food and predators on reproduction and overwinter survival of arctic ground squirrels |
title_full_unstemmed |
The interactive effects of food and predators on reproduction and overwinter survival of arctic ground squirrels |
title_sort |
interactive effects of food and predators on reproduction and overwinter survival of arctic ground squirrels |
publisher |
British Ecological Society |
publishDate |
2000 |
url |
http://hdl.handle.net/1807/355 |
geographic |
Arctic Yukon |
geographic_facet |
Arctic Yukon |
genre |
Arctic ground squirrel Arctic Yukon |
genre_facet |
Arctic ground squirrel Arctic Yukon |
op_relation |
Journal of Animal Ecology (2000) 69, 235-247 http://hdl.handle.net/1807/355 |
_version_ |
1766305108309573632 |