---TITLE: Walrus Monthly Foraging Utilization Distribution in the Chukchi Sea:
2008-2011


---AUTHOR(S):
        Anthony Fischbach
        Wildlife Biologist
        USGS Alaska Science Center Walrus Research Program
        4210 University Drive (Glen Olds Hall room 369)
        Anchorage, AK 99508
        voice: (907) 786-7145


---DATA SET OVERVIEW:
	This dataset describes Pacific walrus (Odobenus rosmarus divergens)
utilization of the Chukchi sea by tracking walruses and their hourly foraging
behavior from June through November using satellite-linked tags during years
of sparse sea ice (2008-2011). To estimate the density of walrus foraging on a
monthly basis, a movement-based kernel density estimator application was used
to predict walrus utilization over a 5 km resolution grid encompassing the
Chukchi Sea. It generated utilization density contours from the gridded
utilization distribution. The utilization density contours are provided for
environmental planning purposes and may only be understood within the context
of the published manuscript. 

     Data is structured by month, which ranges from June through November.
Within each month walrus foraging utilization distributions were estimated by
weighting the kernel density distribution by the amount of time spent foraging
during each recorded track segment. Presented are contour intervals ranging
from 10th to 95th percentile in the geographically referenced Portable Network
Graphic files and shape files referenced below in the related links.

---INSTRUMENT DESCRIPTION:
        Argos Satellite

---DATA FORMAT:
	There are six zip files orderable by month.

--Data Remarks:
       The date range for this dataset is in AST time.

---REFERENCES:
	Related data set at
http://www.arcodiv.org/Database/Benthos_datasets.html (details in Bluhm BA,
MacDonald IR, Debenham C, Iken K (2005) Macro- and megabenthic communities in
the high Arctic Canada Basin: initial findings. Polar Biology (spec. issue)
28:218-231).