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September 2014 | Vol 7 | No 3   

 

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Quail Hatch … Mid-Season Report

By Theron Terhune, Game Bird Program Director

Chicks leaving nestAssessing reproduction at the breeding season midpoint is our first reliable indicator for forecasting fall recruitment and getting an idea of hunting population levels. There are, of course, several routes to decent fall recruitment, such as a very good early hatch followed by a moderate hatch, or a moderate early hatch and a stellar late hatch. In either case, adult bobwhite survival is tightly linked to the extent of reproductive output. To put this into context, reproductive output last season (2013) was not nearly as good as the previous season (2012), but thanks to great overwinter survival, as high as 72% − the highest ever recorded in Albany area during 21 years of year-round telemetry − the end result was a fall population increase. On Tall Timbers, last year’s breeding season started off with good bird numbers (similar to Albany’s) thanks to overwinter carryover, but we observed a lower than average early hatch, and we greatly benefitted from a stellar late hatch, which was the result of good breeding season survival. The upshot is that "dead hens don't lay eggs," but as seen in the past, there is more than one way to produce good fall numbers. This theme seems to hold true for this year’s hatch, at least at the midpoint of the season.

This year nest production is lower than normal on our Albany study site, which is a direct result of lower breeding season survival (see Figure 1). However, the good news is that we are coming off two very good reproductive seasons and decent overwinter survival, so population levels coming into this year are as high as they have been in quite some time. Therefore, it may be another year where the higher number of available breeders may help to offset the lower per capita production. Looking back at 20+ years of research in the Albany area and Red Hills (see years 2004, 2007, and 2011 on Figure 2), it is apparent that the ebb and flow of quail demographics (survival and reproduction) is cyclical even on exceptionally managed sites. Without these long-term datasets, we would be inept at understanding the natural biological cycles of quail populations. Some of our research going forward will be geared toward better understanding these long-term trends, identifying the common biological principles linked to those trends, and understanding how all that translates into improved management action. For now, however, we are optimistic for a good late push of nesting activity in August and September.

On Tall Timbers, nest production is slightly above average, but brood production is way below normal (Figure 1). This is a result of nest success being the lowest it has been in the last 15 years on Tall Timbers. In South Carolina we have observed identical nest production; however, brood production is nearly three times that observed on Tall Timbers (see Figure 1). Predator indices on these sites indicate that predator abundance is roughly four times as high on Tall Timbers, compared to our study site in South Carolina. This underscores the importance of continued predation management for consistent year to year reproductive output; we suspect that properties employing a steady predation management program in the Red Hills are experiencing a good hatch.   

Adult Survival graph

Figure 1. Mid-Summer (July 15) hatch statistics on study sites at Tall Timbers, the Albany Quail Projects, and South Carolina.

On all our study sites, including those in the Red Hills and Albany area, we have observed several pairs and heard plenty of whistling activity over the past couple of weeks, and more recently we have seen an uptick in radio-tagged hens initiating and incubating nests, suggesting that a second wave of nesting is underway. We are hopeful that this late season push will result in a much needed late hatch and produce more birds recruited into the fall population. In years past, nest initiation and incubation of nests occur well in to September; and hatches in the Red Hills and Albany areas are common during late September and early October. If possible,  delaying mowing or chopping to early or mid-October when cutting hunting lanes (grid-blocking) may optimize late season success by reducing the chances of disrupting nests late in the season, and potentially improving survival of late-hatching chicks.

Tall Timbers Bobwhite Fall Density

Figure 2. Fall bobwhite density estimates on Tall Timbers during 2002 – 2013.

The mission of Tall Timbers Research Station & Land Conservancy is to foster exemplary land stewardship through research, conservation and education.