Statewide: This year the statewide index is 17.4 birds/route, a 151% increase from the 2013 estimate (Figure 6). This year’s statewide count is the highest seen in over 6 years dating back to 2008 (Table 4). Every region reported significant increases of 100% or more in pheasant counts, except the NE which report no change in bird numbers compared to 2013. This year’s index is 2% above the 10 year average and -57% below the long term average (Table 4, Figure 4). Iowa research indicates overwinter hen survival, brood survival, and nest success are the major factors influencing annual changes in pheasant numbers. Statewide, the total hens (+142%) and roosters (+53%) counted on routes this year were significantly higher than last year, suggesting excellent overwinter survival AND/OR that poor dew conditions during the 2013 survey lead to a poor count (Table 3 – statewide numbers, Figure 3). Statewide data on chicks (measure of nest success) and age ratios (chicks per adult hen – measure of overall hen success) showed no change compared to 2013. Both indicate the nesting season was very similar to 2013 (Table 3).
This year’s count represents the highest single year increase every recorded in the surveys 52 year history! Within the regions, increases of 200-300% were reported. These increases are beyond the reproductive capability ever measured in radioed wild hen populations. This suggests that counts in 2013 and perhaps 2012 were higher than reported because of drought conditions in August 2013 and 2012 (Figure 3). The small game harvest survey also supports this notion as hunters harvested almost 10,000 more roosters in 2013 than 2012. Dry soils lead to poor dew conditions. Reliability of the roadside counts is highly dependent on heavy dew conditions. Given this information, it is likely the statewide pheasant population was closer to 10 to 12 birds per route in 2013, not the 7 reported (Figure 6- statewide numbers). Thus part of the increase in bird numbers this year is related to birds not counted last year as well as good over winter survival across several regions in 2014. Good soil moisture and thus excellent dew condition also provided for a very good bird count in 2014.
Based on this year’s statewide index of 17.4 birds/route, Iowa pheasant hunters should harvest approximately 200,000-300,000 roosters this fall (Figure 4). Iowa currently has 2.77 M acres of potential pheasant habitat (Table 2). This level of habitat should support an 850,000 rooster harvest, ~80% of this harvest coming from CRP lands. Iowa finally has sufficient hen numbers in most regions to make a recovery from the catastrophic years of 2007 thru 2011, but needs 2 or 3 more good winters and springs back to back to fully recover numbers to what habitat levels can support (Figure 4). It will be very hard to recover Iowa pheasant numbers if significant CRP habitat losses continue in Iowa (Table 2).
Northern Regions: Counts in the NW were the highest in the state at almost 30 birds/rte , while the NE has the lowest densities at 2.7 birds/rte (Table 3, Figure 6). Looking at data in Table 3, changes in adult hen numbers rather than hen success/brood size led to the increased bird numbers in the NW and NC regions – suggesting excellent overwinter survival or last year’s survey did a poor job counting hens. The NE region had
Figure 3. U.S. Drought Monitor soil moisture conditions Iowa mid-August.the longest and snowiest winter of any region which likely explains the lack of any increase (Table 1). Poor dew conditions could also be a factor (Figure 3). Parts of NW and NC Iowa should offer very good pheasant hunting, particularly around public and private lands with good winter habitat (Figure 7). Better counts came from Clay, Dickinson, Emmet, Hancock, Kossuth, Osceola, and Sioux counties.
Central Regions: Counts in the C and WC regions were 2nd and 3rd only to counts in the NW region. Similarly, changes in adult hen numbers rather than hen success/brood size led to the increasing trends in all 3 central regions. Brood size and age ratio data in all 3 regions suggest nest success and chick recruitment were similar to 2013 (Table 3), while below normal snowfall likely led to improved hen survival in the WC region. Better bird numbers were reported in Boone, Carroll, Greene, Guthrie, Hamilton, Iowa, Johnson, Poweshiek, Sac, and Webster counties (Figure 7).
Southern Regions: The southern regions also showed 100 to 200% increases in pheasant numbers although overall densities remain low compared to other regions (Figure 6). The exception was the SE region which reported about 20 birds/rte (Table 3). As seen in other regions, a significant increase in adult hens lead to the higher counts across all 3 regions in 2014 (Table 3). Some of the better counts in 2014 came from Henry, Louisa, Mahaska, Marion, Pottawattamie, and Washington counties.
Statewide bobwhite quail numbers were up significantly (+142%) from 2013 counts (Table 3, Figure 6). Landowners and staff reported more calling males this spring, suggesting good winter survival. This year’s index is 61% above the 10 year average and -33% below the long term average (Table 4, Figure 5). Changing land-use, mainly intensified agriculture, loss of small grain agriculture, and loss of shrubby/brushy habitat are the leading factors in Iowa’s long-term quail decline. This year’s statewide count is the highest since 2004 and 1995 prior to that (Table 4). Better quail numbers were reported in SW and SC Iowa where DNR staff has focused management on providing quail habitat (Figure 7). Iowa has 10,000+ acres of CP33 remaining, a CRP practice that provides needed quail habitat around crop fields in southern Iowa www.iowadnr.gov/habitat . The better quail counts in 2014 came from Adams, Appanoose, Davis, Lucas, Ringgold, and Taylor counties.
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