A little play on Bob Dylan’s famous 60s song about the times – and the waters in our resaca are changing – but not grown like the song says – they’ve dwindled. As the resaca dries up, life on the water is a-changing, too. Less water is bringing in an interesting variation of waterbirds.
The Audubon Annual Christmas Bird Count for the Harlingen Circle was the last day of 2022. It dawned cloaked in fog and mystery. The resaca was covered in an eerie silence as I scanned through binoculars.
I do the feeder watch, which includes the resaca. We live within the parameters of the Harlingen Circle. I spent the week prior to count day identifying the ducks and other new water birds so I knew what I was counting for the tally sheets on the day of the count.
With the low water, gone are the divers like the cormorants, but we have more northern shovelers and blue-winged teal this year than in the past – 14 northern shovelers stayed around for the annual count.
Do you ever wonder what ducks are eating when they swim along half submerged in the water? Well, I was curious because the water is so shallow as the resaca dries up that it’s apparent there is no plant life on that muddy bottom.
I looked up what Northern shovelers eat and found that they are omnivorous, feeding on crustaceans, mollusks, small minnows, insects and their larvae, seeds and aquatic plants. They forage in shallow water over mud bottoms, swimming along with their bill lowered. They love a social feeding event and take advantage of food particles that other swimming or wading birds churn up to the water’s surface. They filter food out of the water with comb like projections, called lamellae, along the edge of their bill. Their bills are seemingly over large, flat and spatulate like. (Chesapeakebay.net and allaboutbirds.org)
Blue-winged teal, the second most abundant duck in North America (behind the Mallard – allabouotbirds.org) numbered eight. Blue-winged teal are dabbling ducks, as are Northern shovelers. Blue-winged teal also are omnivores and feed on vegetative parts of aquatic plants, like algae and duckweeds, seeds of sedges, pondweeds and grasses -- obviously not in our resaca this year so they go for their back-up diet: large amounts of aquatic invertebrates in shallow waters.
Southern Texas and peninsular Florida seem to have the highest number of these winter visitors – the first ducks to fly south in the fall and last to return back north in the spring (ducks.org) – not that we can blame them for loving our Texas winters. They seldom feed away from water, according to Audubon.org.
New to the resaca this year, due to the shallow levels, small waders have flown in and stayed. According to www.iNaturalist.org, we are feeding a couple of long-billed dowitchers and at least one stilt sandpiper along with two avocets https://www.stbctmn.org/post/whose-chick-is-it-anyway and 34 least sandpipers. https://www.stbctmn.org/post/undulating-wave-of-birds
The long-billed dowitcher probes for insects and insect larvae and aquatic invertebrates; sometimes they will probe so deeply their heads will be underwater. They favor freshwater mudflats in their wintering areas. Stilt sandpipers are a bit smaller than long-billed dowitchers and eat mostly aquatic invertebrates such as beetles, snails, marine worms and insect larvae. They may wade belly-deep.
During the very early morning, I saw two killdeers through the binoculars on the distant foggy shore. They are most likely permanent residents. Killdeers are opportunistic feeders, they eat insects, including beetles, caterpillars, grasshoppers, spiders, earthworms, snails, crayfish. They find food by patting the ground or surface beneath shallow water with one foot. They also will probe into mud with their bills and chase prey running along the ground. They’re likely to follow the farm equipment hoping for earthworms. (birdfact.com)
Black-necked stilts, also permanent residents, numbered eight on count day. They eat insects, small crustaceans, worms, and small fish, mostly preferring to stay in the shallow water along the shores.
During a quick break, I saw a really tiny bird in the mesquite branches while I was looking out the kitchen windows. The mesquite limb just outside that window is my bird-feeding station. I thought the energetic little bird was my frequent yellow-rumped warbler visitor – only in a midget size. What a surprise when the bird was identified via iNaturalist.org as a ruby-crowned kinglet. I thought, that can’t be, so I uploaded the fuzzy photo, and it verified quickly as a ruby-crowned kinglet – a first for my trees, as far as I know.
The tiny bird didn’t appear to be eating sunflower seeds but acted more like the Eastern Phoebes, hawking insects while doing aerial acrobatics through the branches. These little ruby-crowned kinglets – wingspan at about 7.5 inches – pick food off tree trunks, branches and dense foliage; they also may hawk or hover to take food. They eat mainly insects, their eggs and larvae and drink tree sap.
I was in for more surprises before I stopped wandering about the acreage at the end of the day. About midday, I was at our fence, searching through the binoculars over the plowed field for any sight of some of the hawks I’d seen the week prior. In the distance, over the thorn scrub, I saw a kettle of vultures. I scanned to the right and saw another kettle and another, so I began counting and kept scanning to the right until I’d seen about 7 or 8 separate kettles and my count was at 200.
Over the resaca was another kettle of about 17 turkey vultures and more on the distant shore – some of them with white legs -- caracaras maybe? I took the best shots I could at that distance and enlarged them on the computer. At least four black vultures were striding along the shore, so that was fun. They were pacing between large, beached catfish – victims to oxygen deprivation possibly, because of the lower resaca waters. And that’s sad. We stock our horseshoe resaca about every three years, just for the birds – if that include vultures, so be it – but it may be time to pray for rain.