2003 Fermilab Bird Report

Winter

Ruddy Shelduck (Photo linked to http://www.lincsbirdclub.co.uk)

The 2002 Christmas Bird Count produced a good on-site species count of 47 and a fairly average individual count. Fermilab site specific highlights included our first count records of Winter Wren and Cedar Waxwing. The former is typically occurs on site as an uncommon migrant and the latter is a summer resident though there have been some recent winter records. Both species have been found with increasing regularity on the off-site part of count. Record high numbers were recorded for Common Mergansers, Common Goldeneyes, and White-throated Sparrows. Once again the results are consistant with increasing numbers through spending the winter on site. All these results are consistent with what one would expect from Global Warming. The count this year also confirmed the expected impact of West Nile Virus on local crow populations. Record low counts were recorded both on and off site. 18 birds were found on site compared to an average of 53 from the previous 10 years. For the entire circle the reduction was even more dramatic; 173 birds were found compared to an average of 1070. The effect, if any, on other species was much less significant. In particular Blue Jay and Black-capped Chickadee numbers, though well down from the record highs recorded last year were not much below the range expected from normal fluctuations.

The remainder of the winter was fairly uneventful though there were several Bald Eagle sightings and some ten or so Long-eared Owls were found inside the Main Ring late in the season. The latter were particularly appreciated since none were recorded on site during the previous winter.

In February we also came across a Ruddy Shelduck on Main Ring Lake! This is a rare eurasian species (the photograph was taken in England) which is also popular with waterfowl collectors and hence birds found in the U.S. are much more likely to be escapees from collections than true vagrants. Consequently, this species was not added to the official Fermilab list.

Spring

Sandhill Cranes

The early spring migration of waterfowl was quite good this year, with all the expected species showing up in reasonable numbers as well as several records for both Tundra Swans and Mute Swans. However, the warbler migration in the late spring was rather disappointing, though there were quite a few records of Pine Warbler in April, and in May there was a Cerulean Warbler and several Orange-crowned Warbler sightings. However, the most significant find of the season was probably the pair of Sandhill Cranes which were present inside the Main Ring and appeared as though they might nest there.

In early April we had an opportunity to assess the affect of Spring burns on displaying American Woodcocks. The south west portion of the ring was burnt in early April when woodcock courtship displays were at their most active. Their activity was monitored before and immediately after the burn. Before the burn the birds could be found on both sides of the trail the divides the southern half of the ring, but were mainly concentrated on the west side where the burn was to take place. On the evening after the burn the birds did return to the area but had moved their display activities to the unburnt section. These observations validated our policy of ensuring that at least one of the southern quadrants is not burnt during the Spring.

Summer

Snowy Egret

This was not a good year for our rarer grassland birds. For the first time in at least years, there were no Upland Sandpipers recorded this year and the number of Henslow's Sparrows on site was much reduced from last year. There were some early sightings in the dog-training area, but in the end the only reliable site was by the wetland mitigation area in ELM-4. Grasshopper Sparrows were also absent from their usual haunts along Eola Rd. However, several pairs had established a new colony on the dirt pile left over from the Main Injector excavation.

Breeding Red-headed Woodpeckers on site have become unusual in recent years and hence it was encouraging to discover several birds hanging out in the dead trees inside the Main Ring in late June and early July. July also brought a new species for the site when a Snowy Egret was seen at the south end of Lake Law.

Fall

Fall migration got off to a promising start this year with a flock of six Hudsonian Godwits turning up at the south end of Lake Law in late August. This is only the second time this species has been recorded on site. Waterfowl migration was also quite good early in the fall with a good variety of species spending tie on Sea-of-Evanescence, however, the late fall migration was something of a disappointment with both small numbers and poor variety occuring during the peak months of October and November. As if in compenstation, there were relatively frequent sightings of Rough-legged Hawks and Northern Shrikes late in the season.