COSEWIC Assessment and Update Status Report on the Cerulean Warbler in Canada
- Assessment Summary
- Executive Summary
- COSEWIC Mandate, Membership and Definitions
- Lists of Figures and Tables
- Species Information
- Population Size and Trend
- Limiting Factors and Threats
- Special Significance of the Species
- Existing Protection or Other Status
- Summary of Status Report
- Technical Summary
- Acknowledgements, Literature Cited, and Biographical Summary of Contractors
- Authorities Consulted and Collections Examined
Limiting Factors and Threats
Factors thought to be limiting Cerulean Warbler populations are well documented in Robbins et al. (1992) and Hamel (2000a).
- loss of mature deciduous forest
- fragmentation of remaining deciduous forest
- changes in forest silviculture practices that result in fewer forests reaching maturity
- loss of important tree species due to disease (e.g. oak wilt) and infestation (e.g. gypsy moth)
- environmental degradation (e.g. acid rain and stream pollution)
- brood-parasitism by Brown-headed Cowbirds.
In Canada, factors 1,2, and 5 are probably the most important.
Very little information exists on Cerulean Warbler migration patterns and habitat requirements. Presumably, they need safe stopover locations close to the coast of the Gulf of Mexico and on the Caribbean coast of Central America. Cerulean Warblers fall victim to light pollution during migration. For example, 93 Cerulean Warblers were killed at a Leon County, FL, TV tower between 1956 and 1966 (Stoddard and Norris 1967).
- loss of humid montane forest
- fragmentation of remaining montane forest
- use of a narrow elevational range
- Date Modified: