11 August 2010

Branch-ing Out

I joined Nannothemis for a trip west. She had a MiBCI meeting south of Coldwater, MI and I decided to skip the meeting and spend time along the Coldwater River in Branch County, Michigan on August 10th.

This county hasn't been sufficiently surveyed for odes through the years with only 27 species tallied in the MOS database and all records before 1964. Thus, it was time to add species and make some updates.

1. My first stop around noon was a great location along the Coldwater River, Riverbend County Park. This clear water river appeared to have much potential with a nice flow and a good mix of substrate (gravel, stones, sand, silty areas at the riverbends).


Given the visible attractiveness, I wonder if agricultural runoff affects the water quality and species richness. The southern border of the park is surrounded by corn fields and posted with signs such as this:


Initially, much of the river access was shaded and only a couple damselflies were out and about. Most numerous were Ebony Jewelwings (Calopteryx maculata), followed by Blue-ringed Dancers (Argia sedula). Here is a male dancer:


Walking the main loop trail didn't turn up any other species, which was curious given the nice-looking habitat.

Heading downstream along a riverside trail, I flushed a darner which perched on the branch of a small tree. It ended up being a male Fawn Darner (Boyeria vinosa):


While poking around a bit more, a male Fragile Forktail (Ischnura posita) and Blue-fronted Dancer (Argia apicalis) were found in the riverside vegetation.

Near the west end of the park, I scanned the opposite, sunlit bank and along came a Dragonhunter (Hagenius brevistylus) with its distinctive J-shape of the abdomen. This was only the third time I've seen one in MI. I worked my way back to another small, sunny location hoping to find the big ode, but found another clubtail instead.


A female Black-shouldered Spinyleg (Dromogomphus spinosus) tapped the water a few times then perched on a leaf nearby:


Retracing the main loop, I had hoped that more sun would be on the riverbanks. No need. I happened upon a female Dragonhunter (H. brevistylus) perched in a small, sunny spot along the trail. I tried to approach for a photo, but she kept flushing and flying to the next sunlit vegetation along the trail. Then around the next bend in the trail, a male Fawn Darner (B. vinosa) flushed and perched on a branch. The next corner produced a coupled pair of the same species (digiscoped through my binoculars):


Surprisingly, I didn't see any river cruisers (Macromia sp.) or hanging clubtails (Stylurus sp.) in this great-looking habitat.


2.
My second stop was the one-lane bridge over the Coldwater River along Stancer Road. A small dam lies under the bridge.


The wide, slow-flow area above the dam provided Violet Dancer (Argia fumpipennis violacea), Fragile Forktail (Ischnura posita), and Blue-fronted Dancer (Argia apicalis) such as this male:


As soon as I arrived on the gravel bar downstream, a Dragonhunter (H. brevistylus) landed at my feet. I snagged this male for a closer view of this large species:


Soon after a second male arrived at the gravel bar:


... and I even saw a third patrolling the river.

3.
The third stop was at Hodunk. A dam downriver from Hodunk Road creates a wide spot in the river and provided many pond species.


Zygoptera included Skimming Bluet (Enallagma geminatum), Stream Bluet (Enallagma exsulans), and Swamp Spreadwing (Lestes vigilax) such as this male:


Anisoptera included Widow Skimmer (Libellula luctuosa), Slaty Skimmer (Libellula incesta), Eastern Pondhawk (Erythemis simplicicollis), Common Green Darner (Anax junius), Prince Baskettail (Epitheca princeps), Eastern Amberwing (Perithemis tenera), Black Saddlebags (Tramea lacerata), Halloween Pennant (Celithemis eponina). Posed is a Common Green Darner (A. junius) exuvia on a grape leaf:


4. & 5. Additional short stops included the Randall Lake Public Boat Launch and Coldwater's Rotary Park for additional pond species including Eastern Forktail (Ischnura verticalis), Blue Dashers (Pachydiplax longipennis), meadowhawks (Sympetrum sp.), and male American Rubyspots (Hetaerina americana):


My afternoon field time was up and I had to return for the MiBCI group dinner.

Nannothemis was envious of a couple of the species observed so we returned to the Coldwater River the following morning. We hoped for good photos due to her superior camera, but the weather did not cooperate. We arrived at the Stancer Road bridge area under cloudy skies and a breeze that kept leaves blowing around. However, there were two Dragonhunters (H. brevistylus) near the gravel bar. Alas, they didn't cooperate. When one did return a bee bumped it from its perch on the rocks and a photo wasn't possible. I did spy a River Cruiser (Macromia sp.) patrolling above the dam, but it didn't come close enough to provide an ID.

Our next try was Riverbend Park, then the storm front arrived and rained us out. We ended up driving home through rain for over 2.5 hours.

Overall, it was a successful, short visit. 13 species were added for the county bringing the total to 40. (only 3 of these are sight-only records) Of course, additional visits during other times of the season and to other habitats would greatly bolster this county's species total.

2 comments:

Cathy Carroll said...

Great post with great photos and explanations.

Darrin O'Brien said...

thanks, Cathy

Hopefully we'll get a few more posts in before the end of the season in MI.