After spending just over a week in the Lower Rio Grande Valley, I returned to the Hill Country with some special memories of the trip that I would like to share. Last week I reported a rare butterfly discovery near Mission that caused much excitement among many butterfly enthusiasts in the area. Last Saturday morning I visited Estero Llano Grande State Park near Weslaco before I opened our vendor’s booth at the Rio Grande Birding Festival in Harlingen at noon. Before leaving the park, I decided to check the flowers blooming around the parking lot in hope of photographing interesting butterflies.

After a few minutes of searching, Jane Crone, a fellow Hill Country birder, spotted an unfamiliar butterfly and called me over to look at it. It didn’t look any spread-wing skipper that I had seen before, so I took a number of photographs to help me identify it. While working in the booth later, I looked through my North American Butterfly field guide but could not find it. In hope of finding an expert on butterflies from the area, I physically searched the attendees at the festival and found a past acquaintance, Dave Hanson. Dave is very knowledgeable about Valley butterfly identification.

To my surprise, when he looked at my photos he said he was not sure what it was. He offered to take one of my photos home and search his reference books and tell me his conclusion on Sunday. In the meantime, I found the butterfly in a Mexico butterfly book identifying it as a Tropical Duskywing. Shortly after the festival opened on Sunday, Dave appeared and excitably told me that this butterfly was the “rarest of the rare” of Valley butterflies. Apparently after I took my photos on Saturday, another person found the butterfly, identified it, and put the word out to the Valley residents.

Dave told me that when he went to the parking lot on Sunday morning, he found around 100 people there trying to photograph it. The butterfly has a second common name, “Common Bluevent.” Dave showed me his photographs showing the butterfly’s blue vent area that I had not seen. I went to the site at 2:00PM, but the butterfly was gone. Twenty people were still there looking for it. Even though Jane and I will not attain fame for our discovery, we were pleased to be there and see the butterfly. This episode illustrates the extreme interest that a small rare butterfly can generate.

Earlier on Saturday morning in Estero Llano Grande, I saw a “river” of Turkey Vultures migrating southward over the park. Likely more than a thousand vultures formed a narrow belt several miles long. Gliding without a wing beat, the birds were riding the north wind southward to the tropics. Cranes, ducks and geese often fly in “V” formations to take advantage of the draft created by the birds ahead of it. Hawks (two were spotted in the procession) rely on updrafts to take them to high altitudes from where they can glide effortlessly for miles. The vultures gave me a firsthand look at their migration technique.

Earlier in the week, I photographed a young Aplomado Falcon on a fence post west of Port Isabel. What was significant about this bird was that it had no leg band, a fact which indicates it was hatched and raised in the wild. Aplomado Falcons are being reintroduced to their former habitat in the coastal prairies in South Texas. Seeing that the birds are breeding in the wild is encouraging as it points to the success of the project.

Rounding my memories was the opportunity to photograph the most beautiful dragonfly I have ever seen, a Mexican Scarlet-tail. This dragonfly has been in Benson State Park near Mission since 2008. To my knowledge it only occurs at this one location in the United States. Its scarlet abdomen and blue thorax can only be appreciated by seeing a color photo – go to the internet and type “Mexican Scarlet-tail dragonfly.” What a week – what memories.



Leave a Comment