Shorebirds of the Bragantinian Peninsula II. Diet and foraging strategies of shorebirds at a tropical site in Northern Brazil
K. Kober
F. Bairlein
Abstract
Being long-distance migrants, many shorebirds have to deal with a variety of habitats spanning a range of climatic regimes within only one year. Although their adaptations to differing environmental conditions are the object of many publications, few investigations have taken place in tropical environments. How do birds cope with the particular ecological setting they encounter on their tropical wintering grounds? In this study we focus on diets and foraging strategies of shorebirds at the Bragantinian Peninsula in northern Brazil during 2001/2002. All species had broad diets with overlapping spectra, no clear clustering according to dietary preference was evident. Indeed, a calculation of theoretical optimal diets showed that a generalistic foraging strategy was most profitable. Larger species were slightly more restricted to large, biomass rich prey, which was profitable because it was readily captured and handled. Since the food stock was scarce as well as temporally variable, we assume that a generalistic and opportunistic strategy would be most optimal. Tidal flats in the wet tropics are commonly subjected to various environmental disturbances such as seasonal volumes of freshwater inflow; it is likely that many have low as well variable food stocks as those of the Bragantinian Peninsula. The opportunistic foraging strategy employed by shorebirds at our study site might therefore also be an appropriate strategy at other tidal flats in the tropics subject to similar conditions.
Cite this activity
Kober K. and Bairlein F. (2006) Shorebirds of the Bragantinian Peninsula II. Diet and foraging strategies of shorebirds at a tropical site in Northern Brazil. 17: 549-562.
@article{Kober2006,
Title = {Shorebirds of the Bragantinian Peninsula II. Diet and foraging strategies of shorebirds at a tropical site in Northern Brazil},
Author = {Kober, K. and Bairlein, F.},
Editor = {},
Year = {2006},
Pages = {549-562},
Volume = {17},
Abstract = {Being long-distance migrants, many shorebirds have to deal with a variety of habitats spanning a range of climatic regimes within only one year. Although their adaptations to differing environmental conditions are the object of many publications, few investigations have taken place in tropical environments. How do birds cope with the particular ecological setting they encounter on their tropical wintering grounds? In this study we focus on diets and foraging strategies of shorebirds at the Bragantinian Peninsula in northern Brazil during 2001/2002. All species had broad diets with overlapping spectra, no clear clustering according to dietary preference was evident. Indeed, a calculation of theoretical optimal diets showed that a generalistic foraging strategy was most profitable. Larger species were slightly more restricted to large, biomass rich prey, which was profitable because it was readily captured and handled. Since the food stock was scarce as well as temporally variable, we assume that a generalistic and opportunistic strategy would be most optimal. Tidal flats in the wet tropics are commonly subjected to various environmental disturbances such as seasonal volumes of freshwater inflow; it is likely that many have low as well variable food stocks as those of the Bragantinian Peninsula. The opportunistic foraging strategy employed by shorebirds at our study site might therefore also be an appropriate strategy at other tidal flats in the tropics subject to similar conditions.},
}
TY - JOUR
AU - Kober, K.
AU - Bairlein, F.
TI - Shorebirds of the Bragantinian Peninsula II. Diet and foraging strategies of shorebirds at a tropical site in Northern Brazil
PY - 2006
SP - 549-562
VL - 17
AB - Being long-distance migrants, many shorebirds have to deal with a variety of habitats spanning a range of climatic regimes within only one year. Although their adaptations to differing environmental conditions are the object of many publications, few investigations have taken place in tropical environments. How do birds cope with the particular ecological setting they encounter on their tropical wintering grounds? In this study we focus on diets and foraging strategies of shorebirds at the Bragantinian Peninsula in northern Brazil during 2001/2002. All species had broad diets with overlapping spectra, no clear clustering according to dietary preference was evident. Indeed, a calculation of theoretical optimal diets showed that a generalistic foraging strategy was most profitable. Larger species were slightly more restricted to large, biomass rich prey, which was profitable because it was readily captured and handled. Since the food stock was scarce as well as temporally variable, we assume that a generalistic and opportunistic strategy would be most optimal. Tidal flats in the wet tropics are commonly subjected to various environmental disturbances such as seasonal volumes of freshwater inflow; it is likely that many have low as well variable food stocks as those of the Bragantinian Peninsula. The opportunistic foraging strategy employed by shorebirds at our study site might therefore also be an appropriate strategy at other tidal flats in the tropics subject to similar conditions.
ER -
