Summary

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Wyckoff, A.M. 1985. Final township maps and potential site frequency summaries regarding longspurs for five counties in Minnesota. Final report submitted to the Minnesota Department of Natural Resources.

Summary:

Food availability can have a significant influence on egg production and size (weight), hatchling growth and survival, and female "fitness" and reproductive effort. In avian populations that forage primarily off territory, breeding site proximity to food resources would be expected to enhance reproductive success. The objective of this study was to determine if: 1) breeding site proximity to "off territory" food resources influences female and/or male territory selection, 2) territory location imparts an immediate reproductive advantage for females (more clutches/season; more eggs/clutch; heavier eggs), 3) territory location imparts a greater fitness for males or females (weight advantage; energetic advantage; higher survival and return rate for the next breeding season), 4) territory location influences hatchling growth, vocalization frequency, and/or timing of fledging, and 5) to locate other relict populations of Chestnut-collared Longspurs in the following counties: Norman, Clay, Grand Forks, Cass, and Polk. By comparing the total potential site frequencies of the 5 counties, it is apparent that Clay County, MN, has the highest potential of longspur habitat, 34.1% of the sections examined contained potential habitat. Grand Forks County is second in potential with 26%, followed by Norman County with 13.9%, Cass County with 8.7%, and Polk County with 9.8%. This pattern of potential distribution is also reflected in the known population distribution for this area.

Cass County (1172 KB)
Clay County (1465 KB)
Grand Forks County (1369 KB)
Norman County (1285 KB)
Polk County (1685 KB)
Traill County (1125 KB)