I stood in the tangled thickets of Frontera Audubon, surrounded on all sides by surprisingly thick fog. Each step I took elicited frantic flaps from overhead. The unusually dense cloud cover and high humidity were keeping the local Turkey Vultures “grounded” this morning, and they seemed unsure of how to handle the situation. The previous evening, I’d watched scores of the buzzards streaming in from all over town to roost in the trees at Frontera. These large birds rely heavily on thermals, using pockets of of rising air warmed by the sun as an elevator system to get airborne and get around. The curious fog that had settled over the Rio Grande Valley was doing the vultures no favors, and the humans traipsing about below added to their apparent uneasiness. Without a sun-assisted lift, they had to flap ponderously to take flight. As I wandered through the park, the vultures took off ahead of me, lumbering through the air to new trees in an effort to evade the terrestrial interloper beneath them. Avian activity levels were low overall, and the birds that were present were hard to see. With no sign of the reported rarities, yet again, Col and I decided to cut our losses and move to a new location.
While we waited for the morning fog to burn off, we traveled to Estero Llano Grande State Park. This haven for wildlife is similar to Santa Ana due to its wide array of different habitat types. Wetlands, woodlands, and just about everything in between can be found within the boundaries of the park, providing food and shelter for a variety of critters. We spent several hours at this site, and the fog maintained its grip on the Valley until the very end. Even though the weather conditions cost us a few sightings, we still encountered no shortage of wonderful wildlife. I spotted a Curve-billed Thrasher as we approached the visitor center, and the feeders hosted the expected blackbirds, doves, and chachalacas. From the observation deck, we had a full but foggy view of the ponds out back. As we watched the various waterbirds feed, we spoke with a helpful ranger who marked some interesting locations on our trail map.
Col and I made our way along the shoreline, keeping track of the different species foraging in the pools. We got decent views of Ringed and Green Kingfishers through the mist as we approached Alligator Lake, an area that felt like a little slice of Florida. A large gator lounged on the shore, while Anhinga and night-herons roosted above. We checked a nearby nest box, but without the sun’s warmth the resident “McCall’s” Screech-Owl had no reason to poke its head out. Following the X on our map, we arrived at a brush pile at the forest’s edge and found our hidden treasure. Two Common Pauraques lay perfectly camouflaged among the debris, resting after a long night of catching insects and ceaseless singing.
I would’ve loved to see Estero Llano in the full sunlight and spend some more time exploring, but Col and I had an appointment to keep at another special spot. The fog finally began to lift and gave us a peek at the entirety of Estero’s beauty as we made our way back along the trail. Thanking the ranger, we returned to the car and headed back into town. We refilled the gas tank and picked up some appetizers before turning east towards Laguna Atascosa National Wildlife Refuge. Bryan has worked at this location for the past few months, and he was able to pull some strings and reserve us a spot on the afternoon Habitat Tour. Laguna A has a 15-mile road looping through a range different natural spaces, but it has been recently been closed to private vehicles due to construction. Refuge officials hope that modifications to the loop will make it less dangerous for the rare Ocelots that hide in the dense thorn forest. With scarcely more than a dozen believed to persist within the park’s borders, the risk of vehicle collisions is too great to leave to chance. As a result, transportation around the loop has been limited to hiking, biking, and guided tours until new routes and safe wildlife crossings are completed. For 3 hours, we were ferried along through coastal prairie, shoreline, and brushy woodlands with a knowledgable refuge guide.
The tour was a fantastic use of our time, and it allowed us to view a large section of the refuge that we otherwise would’ve missed out on. Huge rafts of ducks floated on the lakes and ponds while herons and shorebirds stalked the perimeters. The largest water feature was the shallow, hypersaline Laguna Madre, which hosted spoonbills, pelicans, gulls, and countless Redheads. Col was very excited to see her life Gull-billed Terns, swooping steeply to snag insects in midair. Ascending to a watchtower high on a hill, we had a great view of the surrounding grasslands. From our perch, we could see distant feral hogs and Nilgai, an introduced, invasive species of giant antelope that has taken over southern Texas since escapees from ranches began to breed in the wild. Seeing these two foreign species grazing on the plains made the refuge look like some sort of strange Serengeti.
Laguna Atascosa is well-known among birders as an important conservation area. The Peregrine Fund has used the refuge as a reintroduction site for the Aplomado Falcon, a handsome Neotropical raptor that had all but disappeared from the northern limits of its range. Young birds were gradually released at Laguna, carefully monitored by researchers, and supplied with nest towers that keep out predators. Birds began to breed successfully in the 90s, but the species is still a rare sight north of the Mexican border. We were fortunate enough to spy a pair of Aplomados at their nest platform. Col hadn’t brought her scope on the tour, but our travel companions were kind enough to let us use theirs. Despite the distance and the shimmering heat, we got decent views of the falcons as they scanned the prairie and moved from perch to perch.
We returned from the Habitat Tour to find Bryan waiting for us in the parking lot. He wasn’t totally free of work responsibilities yet, but wanted to share some important information with us. He told us how to get to his house for dinner, and pointed out the area favored by the Crimson-collared Grosbeak, a rare visitor from Mexico that had been seen throughout the winter on the refuge. He also recommended some trails to explore before the sun set. We first admired the local birds at the visitor center feeders before driving out to Osprey Overlook and strolling the path to the Gator Pond. True to its name, the pool was home to a very large American Alligator, as well as a family of Least Grebes and several other species of waterbirds.
Back at the parking lot, I started to outline my ideas for finding the grosbeak out loud. Col humored me, letting me ramble off a coordinated plan of attack to check each location it had been seen in. Suddenly, there it was. Right at the edge of the lot, right in the area Bryan had indicated, right in the tree he said it liked. After missing this species at Frontera Audubon, this was an unexpectedly easy victory. The bird moved through the foliage, feeding as it went and showing off nicely. I was surprised at how much I enjoyed this rarity encounter: the grosbeak’s unique coloration, large size, and accommodating behavior made the observation a real treat.
It took a little bit of backtracking and circling to find our way to Bryan’s house, but we still managed to show up early for dinner. Chips, guacamole, and salsa served as appetizers while we chatted with the other refuge staff about their various projects. Listening to tales of wildlife surveys, interpretive talks, and ocelot tracking made me miss working in the field. Bryan eventually brought out the main course, fajitas with shrimp and Nilgai. In an effort to slow the spread of the invasive antelope, open season never really closes. For what it’s worth, they are delicious.
We went on a night drive with Bryan, who continued to impress us with the special privileges he provided as our “guy on the inside.” Pauraques sang from the darkness all along the road, and we spotted several individuals fluttering through our headlights in pursuit of insects. Rabbits were a constant presence, and we also came across a group of hogs. Our eyes were peeled for Ocelots, but unsurprisingly we did not find any. Bryan and Col glimpsed an armadillo that I unfortunately missed, but we were all treated to stellar views of Barn Owls. At the end of the road, the stars shining overhead were absolutely phenomenal, and the moon was bright enough to read by. The slurred whistles of Pauraques and distant trills of a Screech-Owl echoed through the brush, and the shadow of a Barn Owl sailed through the starry sky. A truly enchanting end to a magical day.
We finally dropped Bryan back at his quarters and said good-bye, returning to our vehicle as the night birds bid us farewell. Driving west towards Harlingen, we tallied up our total species for the day. Even without unidentifiable waterfowl and shorebirds taken into account, we’d managed to catalog over 100 different species between Frontera, Estero, and Laguna. Beautiful scenery, interesting wildlife encounters, and a tasty meal with new friends all added up to make one hell of a day.
Year List Update, February 16 – 239 Species (+ Curve-billed Thrasher, House Wren, Common Ground-Dove, Black-crowned Night-Heron, Yellow-crowned Night-Heron, Anhinga, Common Pauraque, American Avocet, Gull-billed Tern, Aplomado Falcon, Crimson-collared Grosbeak)