by Carl Strang
It has been a while since I posted one of my species dossiers. The idea is to make a record of what I know of a species from my own experience rather than what I have learned from others. This is a valuable exercise. When I got the idea and started it, I was embarrassed by how little I could write even for common species. It has forced me to pay more attention, to observe more, to be more discriminating in what I can claim to know about natural history. Even books and, yes, Internet sources like this blog need to be read skeptically. Today I choose the great blue heron, a species that played an important role in inspiring my interest in natural history studies. Records are dated with my code that begins with the day of the month, followed by a two-letter month code (usually the first two letters of the month’s name) and a two-numeral year. The code 16JE99 would indicate June 16, 1999.
Great Blue Heron
First observed at Hawk Lake, where several fished along the east side each evening in summer during my childhood. These were an early inspiration for my bird watching interest. Also observed in PA, along the Tippecanoe River in IN, in DuPage County, in Florida. Seek food usually in relatively deep water, sit-and-wait foraging. They quickly extend the neck to seize or spear fish or other prey. On rare occasions I have seen them briefly swimming on the surface of water too deep to wade. One in FL waited for fishermen to catch fish, then ran up in hope of getting the catch.
They have loud raucous squawking calls, a brief one in flight (often when disturbed) and a longer more rattling one when handled (i.e. at Willowbrook’s wildlife hospital).
Rookery established around 1967 south of Culver, Indiana, near the Tippecanoe River, in several large sycamores at the edge of a small woodlot near S.R. 17. That site still was used through 1986. Birds appear standing in nests in mid-March, radiate out in many directions to feed. Great blue herons then also reached all parts of DuPage County, IL, despite no rookeries there (a large rookery south of the county at Plainfield).
24JA89. A great blue heron flying east of Lake Maxinkuckee, IN.
10MR00. Several herons have returned to the new, small (10-nest) colony at Danada Forest Preserve.
7MY00. Great blue herons croaking in flight, traveling above West DuPage Woods Forest Preserve. An extended string of them, so the calls may be communication between flying birds.
13NO01. I count 25 nests, now, in the Danada rookery. The trees are at the edge of a pond. They are not sycamores, but I didn’t get close enough to ID. Elm shape.
21FE02. A single heron was standing on a nest in the Danada rookery at 4p.m. The winter has been mild, and it’s not inconceivable that a GBH could have survived the winter locally.
1SE02. At 10:30 p.m., a great blue heron in Geneva, standing in shallow water in the Fox River, apparently fishing in the street lights.
16JE03. This year I know of 2 large nesting colonies in DuPage County, both established in recent years. One is at Danada Forest Preserve, the other at Pratts Wayne Woods, near the intersection of Rt. 59 and Stearns Road and visible from both.
8AU03. I kayaked between Willow Springs Road in Cook County and Route 83 in DuPage on the Des Plaines River. There is a strung-out colony of great blue herons nesting over a 2-mile stretch of river that spans the county line. The nests are in scattered dead trees close to the riverbank, taller than the surrounding trees, 2-5 nests in half a dozen trees total. Though separated sometimes by more than a hundred yards, the trees each seem to have one of the others in view.
28MR06. At Tri-County State Park, the 2 nests from last year (a new satellite of the Pratts Wayne colony) gradually had lost most of their sticks. On the 23rd, herons returned (later than in the larger colonies), and now are building the nests back up. One seen carrying a long thin stick in its beak, flying up to a perch beside the nest and giving it to its mate standing in the nest, who then added it. Two additional pairs perching in those trees, but no new nest starts yet.
18JA09. Danada. Checked great blue heron rookery. Most of the 15-20 nest trees were living cottonwoods, and 90% of the nests were in these. Two were dead trees, and three were willows. One cottonwood had 16 nests, a couple had 13, one had 11. Total nests counted 142. The rookery is in a swampy area around a large pond. Last summer I also learned of a rookery at Churchill Forest Preserve, on the islands in the East Branch of the DuPage River.
11OC10. During a dragonfly monitoring run on the Des Plaines River I noticed that, in addition to the scattered great blue heron nests in tree tops along the shore, there is at least one group of trees with a number of nests in a more concentrated colony. There are more than a dozen nests in at least 3 adjacent trees. This cluster is on the river’s south bank, east of Route 83.