Wednesday, September 4, 2019

2019 Minnesota Pheasant August Roadside Survey decreased 17% from 2018

Summary The 2019 range-wide pheasant index (37.4 birds/100 mi) decreased 17% from 2018 (45.2 birds/100 mi). The brood index and proportion of hens with broods also decreased, and estimated hatch dates were one week later than the 10-year and long-term averages. Severe late-season winter snowstorms, heavy spring rains, and resulting flooding throughout much of the core pheasant range likely impacted nesting activity during the 2019 breeding season. Grassland habitat on private, state, and federally-owned lands increased by 29,903 acres statewide since 2018. The range-wide indices for eastern cottontail rabbitsand gray partridge were similar to 2018 while the white-tailed deer and Sandhill crane indices increased from 2018. The mourning dove index decreased from 2018 and white-tailed jackrabbit observations continue to be historically low across our survey area.

Ring-necked PheasantIn 2019, the average number of pheasants observed range-wide (37.4 birds/100 mi) decreased 17% from 2018 (45.2 birds/100 mi) and was slightly lower than the 10-year average of 41.2 birds/100 mi. The index was 60% below the long-term average of 91.4 birds/100 mi (Table 3, Figure 3A). Total pheasants observed per 100 mi ranged from 8.7 birds in the Southeast agricultural region to 48.8 birds in the WestCentral region (Table 4). The change in the pheasant index from 2018 to 2019 varied greatly statewide with increases in the South Central (24%) and East Central (13%) regions while the Southwest region, a core area of Minnesota’s pheasant range, decreased 32% from 2018. The best harvest opportunities will be in the West Central and South Central regions but hunters will also find good opportunities in the Southwest and Central regions
The range-wide hen index declined slightly in 2019 (6.4 hens/100 mi) compared to 2018 (7.5 hens/100 mi) and was at the 10-year average (6.2 hens/100 mi) but still 54% below the long-term average (13.3 hens/100 mi; Table 3). The hen index ranged from 1.6 hens/100 mi in the Southeast to 9.4 hens/100 mi in the West Central region. The Southwest region saw the greatest decline (46%), while the hen indices among remaining regions were equivalent to 2018.  

The range-wide cock index (6.5 cocks/100 mi) did not change from 2018 or the 10-year average, but remained 40% below the long-term average of 10.5 cocks/100 mi (Table 3). The cock index ranged from 2.4 cocks/100 mi in the Southeast to 8.3 cocks/100 mi in the West Central region. The 2018 cock index increased in the East Central, South Central, and Southeast regions and decreased in the West Centraland Southwest regions. 

The 2019 hen-to-cock ratio (0.98) was slightly below the 2018 ratio (1.16) and still below the long-term average (1.33). The 2019 range-wide brood index (5.4 broods/100 mi) decreased modestly from 2018 (7.3 broods/100 mi; Table 3). The index was similar to the 10-year average (6.4 broods/100 mi). Still, the brood index was 56% below the long-term average (12.1 broods/100 mi). Regional brood indices declined in all regions 2019 Minnesota August Roadside Survey5 except for the South Central, where they remained relatively constant. The brood index ranged from 1.6broods/100 mi in the Southeast region to 7.2 broods/100 mi in the West Central region. The average brood size in 2019 (4.6 chicks/brood) was slightly larger compared to 2018 (4.3 chicks/brood) and equivalent to the 10-year average (4.6 chicks/brood). However, the brood size index remains below the long-term average of 5.6 chicks/brood. The median hatch date (assigned using estimated brood ages from broods observed during the survey) for pheasant broods across their range was 20 June 2019 (n = 204 broods), which was nearly a week later than 2018 (14 June) and the 10-year average (12 June; Table 3).

Declines in the brood index, the number of broods/100 hens (a measure of breeding success), and later estimated hatch dates suggest that severe winter snowstorms, heavy spring rains, and resulting flooding throughout much of the core pheasant range adversely impacted nesting activity during the 2019 breeding season. Though regional and statewide pheasant indices declined, available grassland habitatand habitat quality can help mediate the impacts of annual variation in weather on local populations. Therefore, hunters may encounter good bird numbers where habitat was unaffected by severe weather and flooding, even among regions that exhibited overall declines. Expect that birds will be more difficult to locate in areas where adjacent agricultural fields were too wet to plant and in areas where fall corn and soybean harvest is delayed.

Long term, Minnesota has experienced a gradual but steady loss of habitat, especially CRP, and the impact of these losses correlates well with an overall decline in the pheasant population and harvest since the mid-2000s (Figures 2 & 3A).

Read the full MN DNR article

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