Investigating Food Habitats of Wildlife

How quantify use?

1. Direct observation

2. Captive trials “cafeteria style”

3. Post-ingestion samples (crop, rumen, stomach, cecum, cannula/fistula, dissection, gastric lavage,emetic)

How quantify use?

4. Post-digestion (feces):

Microhistological analysis of plant fragments Hair & animal remains DNA analysis (and new technique - barcoding)

microhistological plant fragments

Photographic Key for the Microhistological Identificationof some Arctic Vascular Plants (SUZANNE CARRIÈRE)

How quantify use?

4. Post-digestion (feces):

Microhistological analysis of plant fragments Hair & animal remains DNA analysis (and new technique - barcoding)

(Martinka and Kendall 1986)

Annual Food Habits of Bears: Proportionate contribution of major food classes to the total annual diet volume of bears in Glacier National Park as determined by fecal analysis, 1967-71 and 1982-85 (n=1514).

(Ecobyte: http://www.ecobyte.com.au/using_.html)

Mammal hair structure:

Hair surface characteristics (scales):

Hair cross-sectional shape:

Examples of reference information:

How quantify use?

4. Post-digestion (feces):

Microhistological analysis of plant fragments Hair & animal remains DNA analysis (and new technique - barcoding)

How quantify use?

5. Remains from feeding (browse surveys, den or nests visits, enclosures, carcass or travel routes for carnivores)

6. Isotope analyses (tissue, hair, breath)

Isotope analyses of tissues:

Different version of elements with different #s of neutrons

Stable isotopes do not decay over time

12C and 14N most commonly used isotopes for diet analyses

Fractionation or discrimination in the ratios of 13C/12C or 15N/14N

Temporal signature in tissue (e.g., bone vs. hair)

Bentzen, T.W., E.H. Follmann, S.C. Amstrup, G.S. York, M.J. Wooller, and T.M. O'Hara. 2007. Variation in winter diet of southern Beaufort Sea polar bears inferred from stable isotope analysis. Canadian Journal of Zoology. 85:596-608.

Idaho Stable Isotope Lab (UI)