Homer Lake Wetland Blog

  Male Common Green Darner Patrolling the Pond Edge The first dragonflies we normally see each year are the common green darners (Anax junius) pictured here. This is because the common green darner is one of several known migratory dragonfly species and these early season arrivals have flown north from somewhere down south long before any of the local dragonfly populations have emerged from overwintering as naiads or eggs (we'll get into "naiads" in a future post).  This year I saw the first common green darners at the wetland last Monday (3/22).  So far I have only seen males, as pictured. As with the frogs, the males have a vested interest in arriving early and staking out their territories so that they are ready to "welcome" any females that show up. In the case of the common green darners they patrol the edges of the pond checking likely spots that a female may choose for egg laying in hopes of finding a mate. I have not yet seen any females but th...

  This time-lapse video condenses 56 hours of frog egg development and tadpoles hatching into just under two minutes (1 minute 52 seconds). That's one frame photographed every minute resulting in 1800 times the real life speed. In addition to showing the boreal chorus frog embryos developing into tadpoles, you will see the algae growing and generating oxygen bubbles and some very small creatures moving around -- there is always more than you bargain for! You will also see that a number of the eggs don't change at all -- they are apparently infertile or otherwise not viable.  In my experimentation with this I found a number of eggs in every batch I looked at to not develop into tadpoles.  I am guessing that the external fertilization that frogs use -- males releasing sperm into the water as the female lays eggs -- may not be 100% effective resulting in some eggs that don't hatch, but that's just my theory on the matter.

Algae in the Pond, 3/22/21 (Can you spot the fairy shrimp? Click photo to view larger) Water Plants Beginning to Grow in the Pond, 3/22/21 (Can you find the isopod?   Click photo to view larger ) Every animal has to eat. The two pictures above show a lush aquatic garden in the pond, perfect for algae and plant-eating pond inhabitants. Contrast that though with the picture below taken just four months prior. There is no water, let alone any algae or pond plants. In an ephemeral pond like this, the whole food chain has to be rebuilt almost from scratch every year, and the timing is of course important. Essentially, the aquatic food web has to be reconstructed from the bottom up so that everything present has something to eat when it needs it.  Detritus, the dead plants and animals and animal waste are the foundation of the temporary pond food web and as you can see in the photo below, dead plant material is ready and waiting for the pond to refill. Algae (which deserves a b...

Painted Turtle at the Wetland Pond, 3/25/21 Today I saw my first turtle of the season at the wetland pond, a painted turtle (Chrysemys picta). I would say that it was sunning itself on the only log in the pond, except that the day was overcast, no sun to be seen. The air and water temperatures were both 56F at the time I was there, so I guess it may have just wanted a change of pace from being wet. There are turtle leeches, though I don't know if they are in this pond, so in addition to sunning themselves for the purpose of regulating their temperature, which would not have been effective today, turtles may also come out of the water for the purpose of inducing the leeches to let go and leave them alone. Turtles in permanent bodies of water spend their winters burrowed into the mud at the bottom of the pond, lake or stream. Believe it or not, they are able to get what little oxygen they need while their bodies are mostly shut down through their butts (technically the...

Surprise that came in with Frog Eggs...   With the permission of the Forest Preserve, I've been borrowing some frog eggs in order to capture time lapses of their development (a project that will be posted to the blog when complete).  Tadpoles are returned to the pond within 24 hours of hatching.  Every time I bring some eggs home though, I am amazed, once again, at the prolific variety of life supported in the pond. Even though I am bringing home just a couple of dead reeds with frog eggs on them, or a dead leaf or two from the bottom of the pond, there are always surprise guests that show up in my videos or time lapses. Case in point: I brought home a dead leaf and a small plant stem with some spring peeper eggs on them, set up my time lapse and was about to start it when I was startled by the critter above undulating through the tank. Yes, it's a leech. This particular leech is about half an inch long when contracted and probably easily over an inch when stret...

Male Red-Winged Blackbird Defending Territory and Calling for a Mate, 3/20/21 Vying for attention with the very loud frogs when I got to the wetland on Saturday were two male red-winged blackbirds perched high in the cattails advertising the territory they had claimed and hoping to attract mates. The field guide I'm looking at (Audubon App on the iPhone) indicates that red-winged blackbirds may be year-round residents here in Central Illinois. If that is the case, then it seems their interest in the wetland is really only for nesting season. They favor wet areas where the females build nests nestled down in the reeds or cattails and both males and females loudly sounding the alarm when anyone wanders near their nesting sites. While my field guide indicates they will eat snails, that's really the only item on the menu mentioned that would favor their hanging out in the wetlands with seeds and insects making up the majority of their diets. Still, the wetland would not be the wetl...

Fairy Shrimp 3/8/21 Though we've already had a look at fairy shrimp ( blog post 3/8/21 ), I had the chance to video the cool swimming motion when I ended up with some fairy shrimp along with the tiny crayfish I wrote about last post.  Check out the video below to see the 11 pairs of legs moving in a wave-like pattern. Almost hypnotic! Also, interestingly, at about 9 seconds into the video the fairy shrimp swims past a floating particle in the water that then gets trapped in the currents generated by the legs and circles around above the fairy shrimp as it swims along. Fairy shrimp legs, in addition to locomotion, also aid in filtering food and respiration. No wonder they need eleven pairs! Fairy Shrimp Swimming, 3/15/21