63rd Lisle Arboretum Christmas Bird Count Results

We had 82 species of birds on the count this year, the 63rd time the count"s been held. This is the third best species total for the Lisle-Arb count, trailing only the counts from Dec 2009 (89 species) and Dec 2006 (86 species). Of course, a significant factor in this was that the weather never got cold for a protracted period leading up to the count, and the temperatures on count day were positively balmy. The high temperature reached 43 degrees on count day.

"Code 4" species, the goodies, included the following.

  • We tallied 22 Cackling Geese, a record high count. This is the 8th year we"ve had this species, but keep in mind that we started paying attention to Cackling vs. Canada only since 2004, which is, well, eight years ago. We"ve had them every year we"ve looked to record the little critters.
  • This was the 10th year for Ruddy Duck to get on the count list, with three this year.
  • We had one Pied-billed Grebe. At the count dinner I thought PBG"s hadn"t been recorded frequently at all, but a look at the count records shows this to be the 12th time for them to make an appearance (once every five years or thereabouts).
  • On the other hand, Horned Grebes ARE rare. The one found at Whalon Lake this year was only the 2nd, with the other being seen in 2008. This one was seen by Donnie Dann, Bob Fisher, Dick Young, Frank Sterrett, Vicky Sroczynski, and Urs Geiser.
  • For the 7th time we counted Double-crested Cormorants. Just one this time.
  • Bald Eagles occur regularly, with the two this year marking the 18th occurrence. We keep them as Code 4 to encourage observers to let me know the age class. Unfortunately, the two this year went into the books as "unaged."
  • We had Merlin on the count for the 7th time, with one this year.
  • We had Peregrine Falcon on the count for the 7th time, with one this year. Didn"t I just say that? Oh, that was for Merlin. Yep, one Merlin, one Peregrine; both for the 7th time.
  • For only the 3rd time, we scored a Virginia Rail. This one was at Hidden Lake, observed by Jenny Vogt. Previous Virginia Rails had been recorded in 2005 and in 1975 (one each in those years). Pete Moxon tells me he believes that Virginia Rails are in the Hidden Lake marsh every winter, at least early in the season, so maybe we should look persistently for them each time.
  • The count circle, or rather the air space above it, was overrun (overflown?) by Sandhill Cranes, Sandhill Cranes, and then more Sandhill Cranes. There were 1367 of them, a record high count among the five years that they"ve been recorded (including this one). We eliminated as appropriate what were thought to be double-counted flocks, but even then I think the numbers seen were but a fraction of what passed through the circle.
  • Barred Owls, now pretty well established in our circle, were tallied for the 7th time, with two this year.
  • A record high count for Pileated Woodpeckers was established, with five reported. This is the 5th year we"ve recorded them, with four of the years occurring in the last 15. Furthermore, the five seen this year constitutes a record high count.
  • The best birds on the count were the two Palm Warblers found by Marlys Oosting and Penny Kneisler. Only once previously (1993) did we have a Palm, and that was just one bird.
  • Last but not least was an Eastern Meadowlark. Though Eastern Meadowlarks had appeared on 21 of the 63 Lisle counts, this was only the 3rd time among the last 15 that that"s happened.

In addition to the record high counts of 22 Cackling Geese, 1367 Sandhill Cranes, five Pileated Woodpeckers, and two Palm Warblers, we also established two other record high counts.

  • Primarily due to the efforts of Greg Neise, we had eight Northern Saw-whet Owls. The previous high tally was two. Interestingly, this previous high of two was reached on five separate occasions: in 2001, in 1999, and in 1993, plus also going back to 1963 and 1954.
  • Maybe not quite as exciting is the fact that our 278 White-breasted Nuthatches was a new record, too. The previous high was 276 of these, in 2009, with 273 recorded in 2010. One two other occasions we topped 200, with all of these during the first decade of the 21st century. This may be a function of observer effort. It would interesting to look at the numbers after normalizing by effort, but we"ll leave that exercise for another time.

Species that we regularly record in decent numbers (say, 25 or more each year), and whose total this year was better than 150% of the 15 year average, include the following:

  • Common Merganser
  • Mourning Dove
  • Eastern Bluebird
  • Pine Siskin

On the low side, the species with totals below 50% of the 15 year average (again limited to species with an average count of 25 or more each year) were these.

  • Canada Goose.
  • Mallard.
  • American Crow. For the 10 years since the steep drop off when West Nile Virus hit, this species has been hovering at around 100 birds each count day. This year we counted 93.
  • American Robin. The 418 we tallied is the lowest total since 1996.
  • European Starling. The count of 1808 represents only the 4th of the last 25 counts with fewer than 2000 Starlings. The other years among these 25 were 2000, 1996, and 1989.
  • Cedar Waxwing. Only 229 this year; the 15 year average is 466.
  • White-throated Sparrow. Just 47 White-throats, our lowest count since 1996.
  • Red-winged Blackbird. This is a species we've struggled to find the last four years. This year we had eight. The previous three years' counts were 1, 6 and 8. The 15 year average is 44.

- Post contributed by Greg Niese

Community, Field TripLindsay Wilkes