Frosty Weekend Poses Only Small Threat to Pheasant Nests

Young pheasant chicks are incredibly vulnerable to death by exposure. The good news is that this weekend's cold snap didn't occur at the peak of hatch.

It's been well-documented that pheasants have had a tough go of it the last few years. We've expired 7 million acres of CRP habitat and are coming off a harsh winter for the birds. For any hope of a rebound, we need to avoid a cold and wet spring. Consequently, this weekend's frosty temps across much of the upper Midwest had me concerned about pheasant reproduction. For a little insight, I called a handful of Pheasants Forever biologists this morning to get their take.

A Warm and Buggy Start to Spring

Across much of the pheasant range, we've had an early and warm spring, which has helped green things up quickly. Although most early nests are established in dead vegetation from the previous year, this year's early green vegetation does offer good cover for nesting hens. Likewise, the early warmth has kicked insect production into gear. While those insects aren't important to hens on the nest, the bugs are critical once the chicks hatch from those eggs. You may be surprised to learn that insects represent more than 90 percent of a pheasant chick's diet during their first week of life and half of the youngster's diet the entire first month. There have been reports of broods in southern Iowa starting on April 30^th this year; that's very early!

A Welcome Lack of Gully Washers

The other major factor in spring reproduction is the amount of precipitation. We need the right amount of rain to green things up, but a gully washer can spell doom. With the loss of big habitat blocks, pheasant hens tend to focus on ditches, roadsides, drainage areas, and other places holding some concealment cover. Unfortunately, these areas tend to gather water during heavy rain events, which results in washed away or submerged nests. So far, it's been a relatively quiet spring across most of the pheasant range for major precipitation events.

A Frosty Weekend

There is some small cause for concern as a result of this weekend's cold temperatures across portions of the pheasant range's northern tier. The issue centers on laid eggs versus the start of egg incubation. For instance, if a hen had laid 8 eggs by Friday evening, but hadn't started the incubation process, then those eggs were likely left unprotected overnight. Pheasant hens don't start incubating their eggs until the entire clutch has been laid. Eggs left unprotected during abnormally low temperatures could potentially chill and die.

Remember I said "potentially;" there are a wide array of factors beyond air temperature that could influence the microclimate at each nest site; including, the amount of grass covering the nest serving as insulation, the soil's temperature below the nest, and upland vs. lowland location of the nest. It's also important to factor in the amount of time the air temperatures stayed low.

If eggs did succumb to the cold during the weekend, then the hen wouldn't be aware of the frozen egg's infertility and would continue to lay her full clutch of eggs. After incubation, only the eggs laid following the low temperatures would stand any chance of hatching. The end result would be a lower number of young-of-the-year birds and an overall decline in the year-on-year population.

However, if the incubation period had started prior to Friday, then the hen's body heat would have protected her eggs from succumbing to the cold temperatures as she sat on the nest. Our hope is that this year's early spring led to an earlier start to the incubation period than normal.

The worst case scenario would be for the very early broods like those reported in Iowa. Young chicks are incredibly vulnerable to death by exposure due to cold temperatures, particularly if accompanied by snow, sleet, hail, or cold rains. The good news is that this cold snap didn't occur at the peak of hatch. Had this weekend's cold front happened in late May, it could have had a monumental impact on chick mortality due to exposure.

My "I'm not a Biologist, but I play one on TV" Reaction

Thankfully, pheasants (and their eggs) are resilient and highly productive, so this weekend's frosty temps probably only had minimal impact in the grand scope of this spring's pheasant reproduction. Keep your fingers crossed for a warm up and light rains through mid June.

The take home message: Even if you stayed at the Holiday Inn Express last night, you simply can't control the weather, but HABITAT remains the knob we are all in control of amplifying. Join your local Pheasants Forever chapter today and start making a difference through habitat restoration and management.

Pheasant Fast Facts (varies by geography)

Average Nest Initiation Day: May 1^st

Average Incubation Start: May 24^th

Average number of eggs in a clutch (nest): 12

Pheasant egg incubation period: 23 days

The peak of pheasant hatch is June 10 to 15

Pheasants chicks can fly short distances by 3 weeks old