Archivos de diario de abril 2016

24 de abril de 2016

Tandy Hills BioBlitz 2016 - Odonata (adults)

I joined iNaturalist maybe a week or two ago and was quickly befriended by @sambiology. He knew of my love of dragonflies and invited to the Tandy Hills BioBlitz to help determine the species of Odonata and other wildlife present at Tandy Hills Natural Area.

Tandy Hills Natural Area is 160 acres with primitive trails and ephemeral streams running through various parts. I learned that it has no permanent water source within park borders but its northern borders (Interstate 30) are less than 300 meters from the Trinity River. I had never to this park before, nor had I really investigated dragonflies in a prairie habitat, so I was excited to see what we might find.

Dragonflies are aquatic insects and spend their first portion of their life developing underwater in ponds, marshes, rivers and other bodies of water. They then emerge, transform into what we know as dragonflies, mature sexually and return to water to reproduce. So...the dragonflies we found here would likely be visitors as most species need to return to a permanent water source to lay eggs. Not a problem though, immature dragonflies usually spend time away from water until they develop and females also generally do not return to water until they are ready to mate. As well, dragonflies don't necessarily roost (think: low-power mode) at night near water.

So before going into this observation I speculated we would see a number of the dragonflies that are very common in the area and that the majority would be immature individuals or females. The adult males (if they were going to be genetically successful) needed to be at whatever habitat (pond, river, etc.) ready to find a female and mate.

Okay, let's not make this too long. Here is what I observed over two days (04.22-23.16):

Anisoptera (dragonflies)
1. Anax junius (Green Darner)
2. Gomphus externus (Plains Clubtail)
3. Pachydiplax longipennis (Blue Dasher)
4. Sympetrum corruptum (Variegated Meadowhawk)
5. Tramea lacerata (Black Saddlebags)
6. T. onusta (Red Saddlebags)

Zygoptera (damselflies)
1. Lestes australis (Southern Spreadwing)
2. Argia apicalis (Blue-fronted Dancer)
3. A. moesta (Powdered Dancer)
4. Enallagma basidens (Double-striped Bluet)
5. E. civile (Familiar Bluet)
6. Ischnura hastata (Citrine Forktail)
7. I. posita (Fragile Forktail)

That's 13 species. I'll be honest--I thought we would see quite a bit more species diversity. There were a number of species I would've bet all the money I have (not very much) on being there...but I found them surprisingly absent. Some things to note are that I did not observe before noon and I walked a lot but definitely did not see the entire park. Observations by others of more species may come in and embarrass me as people process and upload their data.

From my observations the species with the highest densities (in descending order) were S. corruptum, A. junius, G. externus for the dragonflies and E. civile, A. moesta, E. basidens, L. australis for the damselflies. P. longipennis and I. hastata were the least-spotted species. I will write another journal entry with more data breakdown and link it later.

There were two other species I thought I saw late afternoon on Friday but I could not confirm 100% nor did I get a photograph of them. I suspect it was them based on their behavior (way/where they perch, fly, etc.), size and because I felt like the environment was suitable for them at this time of day (away from water and freeway, plenty of cover).

Those species were Erythemis simplicicollis (Eastern Pondhawk) and Pantala flavescens (Wandering Glider). They are both ubiquitous in the area. I suspect that as I return to the park I will confirm these species' presence as well as some others.

It is also important to note that this is in no way a complete list of the the odonate species that inhabit the park. Many species have different flight seasons and some have not even emerged yet but I anticipate they will find Tandy Hills Natural Area a nice place to hang out for a while until they're ready to mate.

Thanks again to @sambiology for inviting me. I had a great time and was very happy to meet so many people who also enjoy nature and getting out and doing stuff. I hope that I can do more BioBlitzs and learn from the other experts while inspiring people to appreciate and treasure the beauty of the nature around us.


Publicado el abril 24, 2016 09:34 TARDE por briangooding briangooding | 3 observaciones | 4 comentarios | Deja un comentario