Saturday, January 9, 2010

One for the Record Book

Tom, Carol, Rick Nirschl, May and Rick Snider

Christmas Bird Count. A compilation of data collected within a 24-hour period by citizen volunteers within a 15-mile diameter called a count circle. All collected data are sent to the National Audubon Society where they are used to track trends in winter bird populations and ranges. Since December 25 1900 when the first 25 CBC’s in the United States and Canada were held, this annual event has grown in scope and size and now includes thousands of count circles in the western hemisphere.
A count day may occur from December 14 to Jan 5. Each count has at least one coordinator. Volunteer counters are assigned routes to tally individual bird species as well as total up numbers of each individual species. Accurately guesstimating numbers in large flocks of geese, ducks, blackbirds or pigeons is not an easy task. It’s much simpler to count birds that typically do not congregate in large flocks. Woodpeckers come to mind. Or trogons if you’re in Costa Rica.
We’ve most always participated in our Appleton CBC coordinated by John Shillinglaw. John has dutifully assembled volunteers, assigned areas within the count circle, and collated data for the past several years. The process doesn’t differ much from CBC to CBC so when we volunteered to do our first CBC here in Texas, (our first non-WI count) we pretty much knew what to expect. The one major difference: We would be counting in a southern climate with the expectation of seeing many more bird species than in Wisconsin in the winter. By the way, John is headed to Texas at the end of this month so we hope to bird with him and his wife Fawn since we missed doing so during this year’s Appleton CBC.
Our Anzalduas-Bentsen count coordinator was Jennifer Owen-White who is with Texas Parks and Wildlife (Bentsen-Rio Grande State Park). We were teamed up with Rick and May Snider, the volunteer park naturalists, along with Rick Nirschl. The “two Ricks” were responsible for discovering the first-ever ABA documented Bare-throated Tiger-Heron.
Weather is always a factor. Too much or too little snow, rain or shine, too cold or too warm, too windy, too foggy…you get the idea. At least in Texas we were not worried about snow. On count day we stepped out of our RV at 5:50 am into 38-degree weather! What the…. We’re in Texas for goodness sakes, not Wisconsin! So much for warm south Texas winter weather.
CBC’s tend to be a bit competitive. In WI the Appleton CBC has usually fared well against other state counts with a total individual species tally usually in the 60’s or low 70’s. By comparison, the Anzalduas-Bensten count has usually finished somewhere in the top twenty. That’s the top twenty in the U.S.

Upper and lower dike roads

view from upper dike road north to reveg area

Every CBC will make an effort to target recently seen rare or unusually occurring birds known to be within their count circle. Our primary target here was a tiger-heron. Given its recent ABA notoriety it would garner a lot of bragging rights. Another sought-after was an Allen’s Hummingbird, a west coast hummingbird well out of its range, which, for the third year in a row, had been showing up at the park’s hummingbird feeders since November.
It was well before sunrise when we joined the Sniders at the dike at 6:00 a.m. where the tiger-heron has typically been seen. Typically seen, but on a schedule all its own as to when. This was THE target bird for our team so we waited in the cold, on the dike, in the dark, for the bird to appear.
Following a walk along the dike to try for other birds (and stay warm) we added Black-crowned Night-Herons and a Common Pauraque. A hoped for Eastern Screech-Owl was a no-show. By 8:00 a.m., with the sun now up in a cloudy sky, the tiger-heron still daned not to appear but other denizens from the swamp next to the levee began to cooperate. Great Egrets and Neotropic and Double-crested Cormorants left their roosts. Four Muscovy Ducks flew past a couple of times but we were not sure if these were locally raised birds. On the opposite dry side of the canal, White-tailed Kites, Northern Harriers, Lesser and American Goldfinches, Red-winged Blackbirds and Great-tailed Grackles were added. American White Pelicans were seen in the distance but still no tiger-heron.
We needed to work the gardens around the WBC for the Allen’s and other hummers so for a time we left the dike behind. The Allen’s was handily found feeding next to the center's gift shop (seen through a window from inside the warm shop thank you very much). Black-chinned, Ruby-throated and Buff-bellied were also added in the gardens. Four hummingbird species seen in a half-hour in the winter? This was not Wisconsin.
Warmed with coffee we headed back over the dike to begin a two-hour hike through a grassy vegetated area, which bordered part of the Resaca. Several more species were discovered including better looks at the four Muscovy’s. In our opinion, they now looked like the real deal. Just past 11:00 a.m. we had circled back and were on the lower dike when Carol yelled, “There it is!” We looked up in time to see the tiger-heron sail across the upper and lower dikes into the reveg field where it usual feeds. Fortunately, Rick Nirschl was near where the bird flew past and he, along with several other tiger-heron hopefuls, confirmed the ID. Much high-fiving. What a bummer it would have been if that bird hadn’t been found on count day!
Following a light lunch we split up to drive/walk further afield. Carol and I took the dike road further west and scouted several other roads in our area to the north. We managed to add other not so typically found birds for the area like Northern Flicker, Groove-billed Ani, and Northern Bobwhite Quail. Lots of raptors including Gray Hawks, White-tailed Hawks and a Peregrine sitting on the top of a radio tower (Tom has a knack for finding Peregrines on towers).

Cooper's Hawk

At 5:30 we regrouped at the center to combine our bird lists with those of our team members. Carol and I managed 81 species on the day. At 6:00 we joined in the post-count potluck hosted at the WBC. Our count circle preliminary tally: 175. If the Muscovy Ducks are accepted then it will be 176. In any event 175 was a new Anzalduas-Bensten count record. And without a doubt our count has the distinction for having the first-ever recorded Bare-throated Tiger-Heron (or any tiger-heron for that matter) on any ABA area CBC.
Some birds were inexplicably missed on count day – like a Ferruginous Pygmy-Owl, which had been seen most every day in the park for the past several weeks. However, bird species not seen on count day but seen during the three days prior to a count day as well as three days after (known as a "count week") may be included. For example Rick Nirschl found a Hook-billed Kite the day after the count and the Ferruginous Pygmy-Owl was also found. Both will be included in the final report but will not be tallied in the count day total.

find the Eastern Screech-Owl

Had it been a sunny, warmer day, no doubt the count could have been higher. Birds, like people, are more active when it’s sunny. But weather aside, it was a terrific opportunity and we're glad we were able to participate. Besides, it got us started well into our 2010 annual list. You know – that lister thing?

Eastern Screech-Owl

No comments:

Post a Comment