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Big Day Birding

by Bob Doe

One of the Bexar County Birding Challenges for this year is to find and identify at least 100 bird species in a single day in Bexar County. Finding 100 species in a day may sound daunting for some, but history has shown that it is possible. It has already been done several times this year. In late April or early May, over 125 species have been found in a single day, and I suspect that a well planned and executed "Big Day" attempt in the county could find 150 species. Although late April and early May are good times to try for a "century" day, there are problems. The number of migrant species is at a yearly high, but the possibility of finding wintering sparrows, ducks, etc. decreases daily.

Big Day birding is more of an exercise in logistics and time management than a challenge of your identification skills. Bexar County has several distinct habitat types, each with representative bird species. To maximize the number of species found, it is generally a good idea to visit as many habitats as possible. Assuming a 10-hour birding day, in order to reach 100 species, you must find an average of 10 species an hour, or a new bird every 6 minutes throughout the day. It is generally NOT a good idea to search for "target" species, unless they are fairly certain to be present and easily found. For example, we all know that Golden-cheeked Warblers are pretty reliably found at Friedrich Park. But to find one may take an hour or more, and there are few other birds readily expected in the park that couldn't be as easily found elsewhere. Friedrich Park is "diversity poor", and probably doesn't make a good "Big Day" stop. Remember, at the end of the day, a House Sparrow counts just as much as a Golden-cheeked.

Here is a suggested itinerary that I believe will give you a good chance of finding over 100 birds in a day. It assumes a 12-hour day (roughly sun-up to sun down, or 7:00 am to 7:00 pm for simplicity) and covers about 100 miles by car. Anytime you are traveling, be alert for birds either in the air or perched on wires and fencelines. As many as 20 percent of your total birds may be "lucky" finds this way, and many common birds are simply assumed to be found this way. This itinerary is only a suggestion; it can be modified in a million ways to include your favorite birding site, or times may be expanded/contracted to meet current conditions. Don't take the suggested times as gospel; adjust according to conditions. If a place is good, spend more time there. If it is dead, move on. But don't get more than an hour or so late.

Start at sun-up (we'll assume 7:00 am) at Avenue A. Primary purpose for this stop is for migrant warblers, vireos, tanagers, orioles, etc., although Avenue A also gives a good opportunity for typical riparian woodland and residential habitat birds. Park as close to Mulberry as possible and walk to the low water crossing and back. Allow about 2 hours.

9:30 AM Eisenhower Park. Expected birds include Western Scrub-Jay and Bewick's Wren. Park in the parking lot and walk along the quarry fenceline as far as the meeting with the paved trail (about a half mile). When you meet the trail, either follow it back down, or return along the fenceline. Eisenhower Park offers an assortment of sparrows, including Rufous-crowned. The athletic fields and fenceline may have Eastern Bluebirds, and the thickets between the parking lot and Military Road can be good. Watch for hawks and both vultures and watch/listen for Northern Raven. Allow 1 hour

10:30 am Go back to Loop 1604 and go west. At the I-10 interchange, take the frontage road exit and go down under the interchange. Observe the swallow colony for Cliff Swallow. Continue west and rejoin the main Loop 1604 going west and south for about 15 miles. About 1.5 miles south of Potranco Road, watch for Cagnon Road (a dirt road, currently marked with a street sign) on your right (if you get to US 90 you've gone about 2 miles too far). 1/2 hour to Cagnon Road

11:00 am Cagnon Road, north of US 90. Cagnon Road traverses some excellent South Texas Scrub habitat. You will begin at the junction between oak woodlands and scrub. Drive slowly, watch and listen, stopping for anything that looks or sounds interesting, until you get to the end of the large field on your left. At the far end of the field, stop and walk down to the bottom of the hill. This stretch can be fantastic! Black-throated Sparrows and Pyrrhuloxia breed in the open scrub to the right, and Bell's Vireo is usually present somewhere along the road. Dickcissel are almost always found in the field, and Painted Bunting are abundant. Long-billed and Curve-billed Thrasher are both regular (Long-billed in the more lush vegetation at the bottom of the hill, Curve-billed in the more open scrubland). Verdin, Roadrunner and Common Ground-Dove are all regular, and Cactus Wren is possible, as are Olive Sparrow and Canyon Towhee. Generally, stop at both the bottom and top of each hill. The scrub habitat under the power lines is good for sparrows. Allow at least an hour.

12:00 At the frontage road to US 90, turn left back to Loop 1604, cross US 90 and turn right onto the frontage road south of US 90 (don't get on the freeway onramp!). At the first road (Cagnon again) turn left and park. Walk along the fenceline up the hill to the water tower, then back down on the other side of the road. Another good area for scrubland species, particularly Curve-billed Thrasher. 1/2 hour

12:30 pm Proceed south on Cagnon to the prison and turn left. At Loop 1604, turn right for about 1.5 mile to a pond on your left. Pull into the drive and scan the pond for ducks and shorebirds. Go across Loop 1604 and turn south down the drive. From the top of the hill, you can scan the far end of a large pond for ducks. Continue down the drive (you're still on public property) to the fence, where you can scan the near end of the pond. Scan the pecan trees for migrants and woodpeckers. Proceed back to Loop 1604, and turn right. Proceed on Loop 1604 south and then east to Somerset Road (about 8 miles or so). Turn left on Somerset to Evans Road. Turn Left on Evans road to the ponds visible on your right. Allow 1/2 hour to Somerset ponds.

1:00 Somerset Ponds. Probably the best shorebird spot available. Also scan for ducks, herons, cormorants. Check marshy area on left side of road. Proceed north to Van Ormy Road and turn right, watching fenceline for sparrows. Take Van Ormy to Somerset and turn left. Proceed to Fischer Road and turn right which becomes Watson Road. Watson traverses open, mixed agricultural land. Look for hawks, Caracara, meadowlarks (primarily Eastern), etc. Watson Road continues to Highway 16. Allow 1/2 hour to Highway 16.

1:30 pm Cross highway 16 and continue on Watson road on the other side (you have to jog just a little). Proceed on Watson to Applewhite and turn right to the crossing of the Medina River. Spend a few minutes in the riparian woodland checking for possible migrants. Reverse your track on Applewhite, pass Watson and continue to Mauerman Road on your right. Turn Right on Mauerman. Mauerman crosses mixed agricultural land similar to Watson. There is a small pond visible on the right just before the sewage treatment plant. Check for possible ducks and shorebirds (probably too far away for ID). Least Grebe has been seen on this pond. Just past the pond is a small sod farm field. Check for shorebirds and meadowlarks. The sewerage plant may have Bluebirds, and possibly shorebirds if there are wet areas visible. Beyond the sewage plant is a large short grass pasture on the left. Watch for sparrows on the fence and listen for Cassin's Sparrows singing. Continue to Pleasanton Road and turn left. 1/2 hour

2:00 pm Continue north on Pleasanton to the causeway over the NW arm of Mitchell Lake. Park just before the bridge and check the wet areas for ducks and shorebirds. Check the reeds for Night-Herons or other waders. Continue north past the Mitchell lake entrance to Loop 410. Stop and check the swallow colony under the overpass for Barn and Cave Swallows (if you still need them). Turn right onto Loop 410 eastbound. 1/2 hour

2:30 pm Exit Loop 1604 at Southton Road and turn right. Continue on Southton about 2.5 miles to Bluewing Road. Turn right on Bluewing. You almost immediately will see sod farm fields on both sides of the road. Scan the fields, especially low damp areas, for shorebirds (Golden, Black-bellied Plover, Upland Sandpiper, Buff-breasted Sandpiper, etc). On the right a short distance is a pond that offers ducks and other shorebirds. You can also scan the sludge basins at the sewerage plant from the road, but be quick. They don't like people with binoculars for security reasons. Return to Southton and turn right. Continue under I-37 and turn right to Braunig Lake. 1/2 hour

3:00 pm Braunig Lake won't have as much variety in the spring as it does during the winter, but it still is worth a visit. Check for ducks, cormorants and pelicans. You should get Pied-billed Grebe and Common Moorhen. Check the wet areas north of the entrance for late Lincoln's, Swamp or Song Sparrows, and the reedbeds south of the entrance for possible Least Bittern. Leave Braunig Lake, turn left, go under the freeway and get onto I-37 south. Get off at Loop 1604 and go east to Calaveras Lake. 1 hour

4:00-7:00 pm Calaveras Lake. Scan the lake for ducks, gulls, terns and pelicans. Work the reedbeds carefully for Least Bittern, Northen Waterthrush, Swamp Sparrow, rails, and Marsh Wren. Watch for herons and egrets, and ibis. Check the cormorants for both Double-crested and Neotropic. The upland thornscrub often has Verdin and Pyrrhuloxia, as well as Curve-billed Thrasher. Calaveras Lake has the POTENTIAL for many species and by the end of the day you will be looking for individuals. Almost anything is possible, so work this area hard.

If you find that you are covering the route too quickly, you can add a stop at Kearny Lake. The willow swamp can be good for migrant warblers and flycatchers particularly. The lake itself is usually not worth the stop. To get to Kearny Lake, exit loop 1604 at Macdona (just south of the Medina River in west Bexar County). Go west on Macdona-LeCoste road for about 1 mile to Kearney and turn left. Proceed about 2 miles to the lake. If you have time at the end of the day, you might check Southside Lions Park or Espada Park.


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