Effects of Conservation Reserve Program field age on avian relative abundance, diversity, and productivity

  • Published source details Millenbah K.F., Winterstein S.R., Campa H., Furrow L.T & Minnis R.B. (1996) Effects of Conservation Reserve Program field age on avian relative abundance, diversity, and productivity. The Wilson Bulletin, 108, 760-770.


This study is summarised as evidence for the following.

Action Category

Restore or create grasslands

Action Link
Bird Conservation
  1. Restore or create grasslands

    A replicated study in summer 1992 in 19 CRP fields in Michigan, USA (Millenbah et al. 1996), found that more bird nests were found in older fields and that they had higher survival rates than those in younger fields (average of 22-23 nests/field and 28-29% survival for nine 4-5 year-old fields vs. 10 nests/field and 14% survival for three one year-old fields). However, bird species diversity was higher in one-year old fields, compared with four or five year-old fields. Bird abundance varied over time, with no clear pattern. A total of 32 bird species were recorded, with red-winged blackbirds Agelaius phoeniceus, song sparrows Melospiza melodia, bobolinks and sedge wrens being the most common. The majority of nests (83% of 166) found were red-winged blackbirds’.


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