The relationship of blue crab abundance to winter mortality of Whooping Cranes

Autor: Michael J. Baldwin, Bruce H. Pugesek, Thomas V. Stehn
Rok vydání: 2013
Předmět:
Zdroj: The Wilson Journal of Ornithology. 125:658-661
ISSN: 1938-5447
1559-4491
DOI: 10.1676/12-159.1
Popis: We sampled blue crab (Callinectes sapidus) numbers in marshes on the Aransas National Wildlife Refuge, Texas from 1998–2006, while simultaneously censusing the wintering population of Whooping Cranes (Grus americana) on the refuge and surrounding habitats. This was done to determine whether mortality of wintering Whooping Cranes was related to the availability of this food source. Yearly variation in crab numbers was high, ranging from a low of 0.1 crabs to a high of 3.4 crabs per 100-m transect section. Significant non-linear increases in both juvenile and adult mortality in relation to decreasing crab abundance was observed. Results suggest that some threshold of crab abundance exists in which Whooping Cranes have higher survival on their wintering grounds.
Databáze: OpenAIRE