Using digital photography to examine grazing in montane meadows

Rangeland Ecology and Management
By: , and 

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Abstract

Cattle (Bos taurus) numbers on national forests are allocated based on allotment grazing capacity, but spatial patterns of timing and density at smaller scales are difficult to assess. However, it is often in meadows or riparian areas that grazing may affect hydrology, biodiversity, and other important ecosystem characteristics. To explore real-time animal presence in montane meadows we distributed 18 digital cameras across nine sites in the Sierra National Forest, California. Our objectives were to document seasonal and diurnal presence of both cattle and mule deer (Odocoileus hemionus), identify the effects of three fencing treatments on animal distribution, and test digital photography as a tool for documenting cattle presence. We recorded 409 399 images during daylight hours for two grazing seasons, and we identified 5 084 and 24 482 cattle "marks" (instances of animal occurrence) in 2006 and 2007, respectively. Deer presence was much lower, with 331 marks in 2006 and 598 in 2007. Morning cattle presence was highest before 0800 hours both years (13.7% and 15.4% of total marks for 2006 and 2007, respectively). Marks decreased until 1100 hours and then increased around 1400 hours and remained relatively stable until 1900 hours. Marks then rose precipitously, with >20% of total marks recorded after 1900 hours both years. Deer presence was less than 10% per hour until 1800 hours, when >20% of total marks were recorded after this time both years. Among treatments, cattle marks were highest outside fences at partially fenced meadows, and deer were highest within completely fenced meadows. Our experience suggests that cameras are not viable tools for meadow monitoring due to variation captured within meadows and the time and effort involved in image processing and review.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Using digital photography to examine grazing in montane meadows
Series title Rangeland Ecology and Management
DOI 10.2111/REM-D-09-00130.1
Volume 64
Issue 2
Year Published 2011
Language English
Publisher Society for Range Management
Publisher location Wheat Ridge, CO
Contributing office(s) Forest and Rangeland Ecosystem Science Center
Description 9 p.
Larger Work Type Article
Larger Work Subtype Journal Article
Larger Work Title Rangeland Ecology and Management
First page 187
Last page 195
Time Range Start 2006-01-01
Time Range End 2007-12-31
Country United States