Journal
ECOLOGY
Volume 96, Issue 6, Pages 1586-1597Publisher
WILEY
DOI: 10.1890/14-2027.1
Keywords
fire ecology; forage maturation hypothesis; grassland; grazing; nutritional ecology; tallgrass prairie; transient maxima hypothesis
Categories
Funding
- NSF/DEB [1020485]
- NSF Konza LTER
- Division of Biology, KSU
- KSU NSF GK-12 program [DGE-0841414]
- Direct For Biological Sciences
- Division Of Environmental Biology [1020485, 1440484] Funding Source: National Science Foundation
Ask authors/readers for more resources
Foraging decisions by native grazers in fire-dependent landscapes modulate the fire-grazing interaction. Uncovering the behavioral mechanisms associated with the attraction of grazers to recently burned areas requires understanding at multiple spatial scales in the ecological foraging hierarchy. This study focused on feeding in the area between steps in a foraging bout, the feeding station, as forage chemistry and vegetation architecture play central roles in these fine-scale, feeding-station decisions. The forage maturation hypothesis (FMH) uses the temporal dynamics of forage quality and quantity in grasslands to explain the distribution of large herbivores, but does not address herbivore responses to inter-patch variation caused by fire-induced nutrient increases of forage quality. Using an experimental setting with contrasting fire treatments we describe the effects of variable burn history on foraging kinetics by bison at Konza Prairie Biological Station (KPBS). We assessed the potential to link the FMH in a complementary fashion to the transient maxima hypothesis (TMH) to explain temporal variation in bison responses to grassland forage quality and quantity in response to burning at different temporal frequencies. Forage attributes met predictions of the TMH that allowed us to investigate how forage maturation affects feeding station foraging behavior across watersheds with varying burn frequency. At sites burned in the spring after several years without burning, both bite mass and intake rate increased with increasing biomass at a greater rate during the growing season than during the transitional midsummer seasonal period. In these infrequently burned watersheds, early growing season bite mass (0.6 +/- 0.05 g; mean +/- SE), bite rate (38 +/- 1.5 bites/ min), and intake rate (21 +/- 2.3 g/min) was reduced by similar to 15%, 13%, and 29% during the midsummer transitional period. A behavioral response in foraging kinetics at the feeding station occurred where a nonequilibrial pulse of high-quality resource was made available and then retained by repeated grazing over the growing season. Our results provide the first experimental evidence for demonstrating the fine-scale behavioral response of a large grazer to fire-induced changes in forage attributes, while linking two prominent hypotheses proposed to explain spatial variation in forage quality and quantity at local and landscape scales.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available