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Showing posts from March, 2021

Enter the Dragon(fly)

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  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 they'll

Frog Egg Development : Boreal Chorus Frogs (time-lapse video)

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  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.

Timing is Everything / Dinner is Served

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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 blog post of it

New Arrivals

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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 their "cloaca

Surprise! (video)

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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 stretched out. It has

Red-Winged Blackbirds

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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 Revisited (video)

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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

Tiny Crayfish

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Tiny Crayfish from the Wetland, 3/15/21 "Crawdads" is what we called them where I was growing up, but they have many other interesting regional names as well. Scientists recognize some 600 species of crayfish worldwide, of which 375 are found in the United States and 23 in Illinois. Like the fairy shrimp and the isopods, crayfish are crustaceans. The family resemblance to lobsters is unmistakable, though lobsters strictly inhabit saltwater environments and crayfish freshwater. This little guy is no doubt newly hatched this spring. Crayfish have an interesting technique for caring for their young. Female crayfish "cement" their fertilized eggs under their tails and when they hatch, the young continue to cling there until after their first three moults when they are big enough to fend for themselves.  The photo at the bottom of the page was taken at Homer Lake this Spring, though at a different temporary wetland, a flooded field in the middle of the woods which I foun

Clean-Up Duty

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Fresh-Water Isopod from the Homer Lake Wetland  Monitoring my underwater camera from my iPhone, I saw a bizarre looking little creature making its way over the bottom of the pond, like a miniature tank over the terrain. I only caught a glimpse before it was out of sight but grabbed my net to see if I could get a better look.  The photo above shows the larger of the two that came up along with a dozen or more fairy shrimp and one very small crayfish (more on the crayfish soon). If you think about where you've seen something like this before, if you do any yard or garden work, you may very well be reminded of the little roll'em-up bugs (or "pill bugs" or "sow bugs" or "woodlice") that are easily found in moist soil and under rocks, etc... and for good reason because they are related.  Both the pill bugs of your garden and this creature from the bottom of the wetland pond are isopods, which like the fairy shrimp we've already seen and the crayfish

Freezing Frogs

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View of the Wetland with Ice on Plants and Trees, 3/15/21 Overnight the temperature plummeted and today has been hovering just above freezing. During the two hours I was visiting the wetland, the temperature warmed from 33F to 36F with the wind chill about 10 degrees colder.  The water temperature when I arrived was 42F. Not surprisingly, in contrast to all my other visits over the past two weeks, there was complete silence when I arrived. The silence was interrupted briefly by the honking of a couple of geese who took off as I approached the pond (is there a pair thinking of setting up house at the wetland this year?).  Eventually there were brief bouts of one or two spring peepers making a brave attempt to attract a mate, but these never lasted more than a couple of minutes with no more than three frogs joining in at the most, long periods of silence in between. I was dressed in two or three layers but still cold. The frogs, of course, were completely exposed to the temperature aroun

"Familiarity Breeds Contempt"

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Canada Geese visiting the Wetland, 3/10/21 Yes, Canada geese. It's easy to be so immune to such common animals or even annoyed by them, and certainly they can be a nuisance. Nevertheless, they have their own beauty, interest and role to play. At the wetland I see them only sporadically and in the years I've been visiting the wetland have never seen them take up residence. They seem to come only as visitors here.  When I arrived on Wednesday (3/10), this pair was making themselves at home. One of them was seemingly finding plenty of food to keep it occupied with its head underwater (see photo below) while the other kept its eye on me throughout my visit until they eventually decided to go somewhere else. I wondered what the one was finding to eat. I read that they are primarily vegetarians, so perhaps things are greening up down there. Around the edges I did see a little bit of green on this visit, so I'm guessing that was it. One goose kept an eye on me while the other seem

Spring Peepers Pair and Egg

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Spring Peeper Egg, Homer Lake Wetland 3/10/202 Doing "my homework" last night, I learned that in contrast to many frog species that lay their eggs in large clusters (some of which we will see this year), spring peepers lay their eggs singly along plant stems. Today at the wetland I spotted a pair of spring peepers together (photo below) and checked the dead reed they were on and sure enough found four or five eggs spread out along the length of it, one of which is shown above.  Female spring peepers have their work cut out for them in that they lay from 800 to 1000 eggs. Spreading them all out must require a fair amount of "leg work" but presumably avoids the proverbial problem other frogs may encounter of "putting all their eggs in one basket." Incidentally, you may notice one of our friends, the fairy shrimp, photobombing in the top right corner of the photo below. S Pair of Spring Peepers, 3/10/2021

Fairy Shrimp

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Fairy Shrimp from the Homer Lake Wetland Although these creatures look like concept drawings for characters in a yet-to-come Star Wars movie, they are actually small fresh-water crustaceans (think crabs, lobsters and shrimp) that inhabit ephemeral (temporary) ponds. You may rightly wonder how a fully aquatic animal such as the fairy shrimp survives from year to year in ponds that dry up completely most years. It is, after all, the fact that they dry up completely on a regular basis that makes them unsuitable habitat for fish and it is the absence of fish that makes such ponds particularly attractive for many other types of animals such as spring peepers, chorus frogs and the fairy shrimp.  So how do fairy shrimp survive when there is no water?  Female fairy shrimp lay two types of eggs. One type has a thin shell and will hatch the same season that it is laid. The other type has a much tougher outer covering and will not hatch until the pond has dried out and then has water again.  This

Boreal Chorus Frog (video)

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Boreal Chorus Frog calling from the shelter of a tangle of dead plants, 3/3/2021 If you look closely at the picture above you can see a small frog tucked under the triangle of dead plant stems with his throat ballooned out to amplify the sound of his call.  This was one of a handful of boreal chorus frogs ( Pseudacris maculata ) that was calling along with the huge chorus of spring peepers at the Homer Lake Wetland on 3/3/21.  The numbers of chorus frogs will grow in the coming days and may even come to rival the number of spring peepers, though the high shrill peeps of the peepers will still probably dominate the audioscape.   If you take a look at the short video below, you will hear and see the chorus frog above doing his best to be heard above the din of the spring peepers. You will be able to tell the sound of the chorus frog because his throat enlarges with each of his calls and his call is very different from that of the spring peepers. The call of the chorus frogs is usually co

Spring Peepers (video)

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Male Spring Peeper calling at the Homer Lake Wetland 3/3/21 If you've been anywhere near the Homer Lake Wetland in the past few days or have occasion to pass by in the near future, you're quite apt to hear a near-deafening high-pitched raucous.  This is the sound of hundreds, perhaps thousands, of male frogs competing for female attention.  Amazingly, all these decibels come from frogs only about one and a half inches long.  Currently  the predominant species heard is the aptly named spring peeper ( Pseudacris crucifer* ), whose main call is an insistent "peep," though there is a less often heard aggressive variation that has more of a brief trill to it. These little critters spend their lives off in the woods but like most, if not all other frog species, require water for breeding. They get a jump on things (sorry) by starting as early in the spring as the weather allows, which is still surprisingly chilly considering the fact that they do not generate their own bod

Life of the Wetland

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  Main Pond at Homer Lake Wetland 3/1/21 In my years of visiting and observing the Homer Lake Wetland, I've marveled at the abundance and variety of life that it supports. What is even more surprising though is the fact that the wetland has a life of its own. Pictured above is the main pond of the wetland today, the first day of March, 2021. Melting snow and late winter rain have gifted it with an abundance of water. This is in stark contrast to its appearance just two months ago at the end of December. Main Pond at Homer Lake Wetland 12/26/20 At the end of December there was only a small wet area in the center of the pond area.  Only nine days later, the water level had already significantly increased. Main Pond at Homer Lake Wetland 1/4/21 This was the end of a four-month dry spell as evidenced by the photo below taken at the end of August. Main Pond at Homer Lake Wetland 8/24/20 I haven't kept a close eye on the pond to know if it goes completely dry every year, but I do kno