Category: fish

Readers’ wildlife photos

June 6, 2020 • 8:00 am

During the pandemonium surrounding the entry of Honey and Dorothy’s broods into Botany Pond at the beginning of May, reader David Campbell sent me some wildlife pictures. And, as sometimes happens, I forgot to put them in the “readers’ wildlife” folder. He reminded me, and, with apologies, here are some late photos. David’s captions are indented:

Descriptions follow.  The Cannon Spring photo [last one] is not the highest quality but the situation was so unique that I thought some of your readers would be interested.

Dog Puke Slime Mold (Fuligo septica) A plasmodial slime mold that frequently occurs on mulch around plants after heavy rains.  The gross factor made it a big hit with my students when it appeared in the ornamental plantings outside my classroom.  It has no odor.  I am waiting for someone to come up with a Hairball Slime Mold.

Sailfin Catfish, Pterygoplichthys sp. Photographed in Silver Glen Springs in the Ocala National Forest of Florida.  Sailfins are exotic invasives that I have seen in a lot of springs in the St. Johns River basin.  Two species of Pterygoplichthys are found in Florida and frequent hybridization makes identification to species difficult.  Sailfin catfish are edible but they are encased in a hard, bony armor so cleaning them is difficult.  Some people simply cook them “in the shell” and peel them apart.

Blue Crab (Callinectes sapidus).  Blue crabs are anadromous, occurring in both fresh and salt water.  This one was photographed about 15 feet below the surface at the mouth of a freshwater spring in the Ocala National Forest.

Florida Gar (Lepisosteus platyrhincus) Gars look intimidating but are not aggressive toward swimmers.  This meter long fish swam over to examine me and then went back under nearby overhanging vegetation to do what gar seem to spend most of their time doing, sitting motionless in the water column.

Green Fly Orchid (Epidendrum magnoliae).  A native epiphytic orchid that is found as far north as North Carolina.  Different plants bloom at different times of the year, sometimes as late as December in Florida.  The flowers are quite small and easily overlooked but worth the effort to find.

Sidewinder (Crotalus cerastes).  Photographed in Arizona.  This is one of the smaller rattlesnakes and this individual was typically nervous and aggressive.  The right infrared sensing pit is visible forward of the eye.  Like many other pit vipers, sidewinders hunt at night and use infrared radiation from homeothermic prey in the final localization stage of hunting.

Monarch Butterfly (Danaus plexippus).  Two photos of a chrysalis, the pupa of this familiar butterfly.  These photo were taken three days after pupation.  The first photo was taken using conventional front lighting.  Clearly visible in the “skin” of the pupa are the outlines of wings, antenna, respiratory spiracles, and abdominal segmentation.  The second photo, taken during the same session, shows the chrysalis backlit.  Notice that the lower two thirds of the pupa is translucent with little or no visible structure.  Small clusters of cells are already organizing development of major butterfly organs and tissues from the products of broken down larval tissues.

Unicorn Caterpillar Moth (Schizura unicornis).  This is one of the more unusual Notodontidae caterpillars and was found feeding on an antique rose in the garden.  I moved it to a less valuable Cherokee rose where it continued feeding.  The adult is a nondescript little moth with a 25-35 cm wingspan.

Cannon Springs, Ocklawaha River, Florida.  This is a grab shot of something that is only visible for a month or two every three to four years.  Back in the 1960s the Army Corps of Engineers conceived and began construction on a barge canal connecting the Gulf of Mexico with the Atlantic Ocean, cutting across the Florida peninsula around the same latitude as Ocala.  One of the most beautiful rivers in Florida, the Ocklawaha was dammed to provide a wider and deeper channel for barges using the canal.  The resulting reservoir covered more than a dozen freshwater springs including several large ones.  President Nixon halted the canal construction before it could be finished but the dam remains and attempts to dismantle it and begin restoring the river have failed due to political resistance.

Every three to four years the Corps draws down the water level in the reservoir and, for a few weeks, several of the “lost” springs reappear.  Cannon is one of them.  I had planned on snorkeling here to photograph the fish and spring but I was the only human within miles and I never swim alone, especially when there is a five foot alligator sunning on the bank.  This photo was taken by holding the camera underwater as I floated nearby.  The larger of the two spring basins is in the background including the two vents where water flows out fast enough to keep the limestone clear of debris.  Also visible are several species of fish including lake chubsucker (Erimyzon sucetta), largemouth bass (Micropterus salmoides), chain pickerel (Esox niger), and bluegill (Lepomis macrochirus).  The spring is now submerged beneath four additional feet of murky brown water and won’t be visible again until at least 2023.

OLYMPUS DIGITAL CAMERA

 

Juvenile striped eel catfish form a coordinated, roiling ball to avoid predation

January 27, 2020 • 1:15 pm

Both Matthew and reader Dom sent me this link to The Colossal describing and showing another amazing animal behavior, this time in the striped eel catfish (Plotosus lineatus), a smallish species (average size about 14 cm) found in the Indian and Pacific Oceans, as well as the Mediterranean where it’s a recent invader. It’s the only catfish associated with coral reefs.  It’s also venomous, with a poison spine on the dorsal fin and each of the pectoral fins, which is reported to have been “fatal”, apparently to at least one human.

While adults are solitary or occur in small groups, the juveniles form schools like the one shown below, comprising 100-150 individuals.  As the report below recounts (click on screenshot), and the videos underneath show graphically, the youngsters swim in roiling balls of fish, with each individual heading towards the bottom and then back up again. (The video was filmed in Bali.) They apparently gather like this for protection, as younger fish are only lightly venomous and could be taken by predators who apparently avoid adults. (Note the striking striped coloration, which may well be “aposematic“: a pattern warning that the bearer is dangerous or distasteful.)

Why they move down and up again is anyone’s guess. I had two ideas: it gives everyone a chance to forage on the bottom while they stay together as a mass, or it makes their pattern more obvious to predators. Or it could be both.

The video comes from the Abyss Dive Center in Bali:

I found another two-minute video that also suggests that they move like this so all individuals can forage.  And be sure to see what happens one minute in, when they rise from the sea floor all together, writhing like a giant jellyfish:

Here are two photos from the Monaco Nature Encyclopedia. The first is an adult, the second a school of juveniles hiding in a reef.

© G. Mazza

 

© Sebastiano Guido

Readers’ wildlife photos

October 13, 2019 • 8:00 am

Today’s photos of animals, all from diverse groups, come from David Campbell, who relates a scary mallard story too—though it turns out all right. David’s captions and tales are indented:

Another batch of photographs.  The duck narrative has a happy ending although I didn’t expect one when it happened.
Mantispid (Dicromantispa interrupta). Convergent evolution at work.  This delicate little predator, a close relative of ant lions and lacewings, was found in Clay County, Florida.  I submitted this photo because I dimly remember PCC(E) saying he was thinking of a post on mantispids.  Maybe the photo will serve as a gentle nudge. [JAC: These are mantidflies in the order Neuroptera rather than Mantodea, like the mantises we know and love.]
Great Golden Digger Wasp (Sphex ichneumoneus) photographed while digging a burrow near Gainesville, Florida.  When I got too close to where she was working she took off and hovered a couple of feet in front of me and, facing me, flew in a sidewise pendulum arc for 15 to 20 seconds until I backed away.  When she resumed digging I returned to my original position and she ignored me from then on.  In general, I find that solitary burrowing wasps are nonaggressive toward humans who don’t do something to antagonize them like stepping on, grabbing, or swatting them.
Striped Bass (Morone saxatilis) photographed at Silver Glen Springs in the Ocala National Forest, Florida.  Stripers are anadromous, spending most of their lives in saltwater but breeding in freshwater.  In late summer they congregate in large schools at Silver Glen, more than 70 miles up the St Johns River from the Atlantic Ocean.  I have also found blue crabs, flounder, striped mullet, and southern stingrays there.

Citrine Forktail (Ischnura hastata) male.  North America’s smallest damselfly, it was photographed on a chicken-wire fence.  This is a New World species but there is a disjunct population in the Azores that apparently arrived in the late 19th century.  The Azores population reproduces by parthenogenesis, a process previously unknown in odonates. For the curious, there is a paper from Nature describing the investigation.

Mallard (Anas platyrhynchos) photographed at Glen Park in Williamsville, NY.  The stream is channeled with stonework retaining walls along much of its length.  A few seconds after this picture was taken the hen and duckling moved up against the retaining wall.  I watched as the duckling suddenly vanished, pulled down from below.  The hen squawked and fluttered and maneuvered her remaining 7 offspring to the opposite bank.

I was pretty sure what had happened because I spent a lot of time in college working near a large beaver pond and had seen snapping turtles grab young ducks.  I reacted from my gut and not my head (I probably didn’t need those fingers, anyway.) and reached down to try to find the duckling.  There just didn’t seem to be enough room at that spot for a large snapping turtle.  30 seconds of feeling around located nothing but weeds and water.  I stood up and looked at the remaining mallard family and, when I looked down again, there was a duckling motionless a few centimeters below the surface tangled in weeds.  I reached back down, found nothing restraining it but the weeds, and brought it back to the surface.  It sputtered a good deal but was soon breathing on its own.  Unfortunately, its feathers were so waterlogged that it couldn’t swim.

The hen fled every time I tried to approach so I left junior in very shallow water surrounded by aquatic plants for cover and support and went on my way hoping that a reunion would soon happen.  Thirty minutes later I passed by the spot and the duckling hadn’t left cover and mom and brood were 35 meters downstream oblivious to the racket produced by her abandoned offspring.  I collected the mostly dry duckling and released it on a flat  section of bank just downstream of the rest of the group.  Within a few minutes all was well again.  I suspect that a turtle did grab the duckling and something either distracted it (me?) or this duckling was too much for a small turtle to subdue and so was released.

JAC: What a nice thing to do!

Mojave Rattlesnake (Crotalus scutulatus) photographed near Ajo, Arizona. This is one very angry and very dangerous snake.  Most North American pit vipers have a venom that is primarily hemotoxic but many Mojaves have a strong neurotoxic component that gives their venom an LD50 ten times more potent than most other rattlesnakes.  A similar variation has evolved in the canebrake rattlesnakes near my Florida home.

Readers’ wildlife photos

September 30, 2019 • 7:45 am

Stephen Barnard, whose photos may have initiated this regular feature, has been taking a break and fishing. But today he’s back with a new batch of pictures of birds, fish, and flies. His captions are indented.

All photos except the last are in chronological order.

Sandhill Cranes (Grus canadensis) This time of year they gather in flocks, preparing for migration. (They breed here.) The first few photos show what I think is a friendly interaction.

I’ve included photos, mixed in, of the three species of trout on my place: rainbow trout (Oncorhynchus mykiss), brown trout (Salmo trutta), and brook trout (Salvelinus fontinalis). Rainbows are by far the most numerous in the creek. However, in the ponds the browns dominate and get very large by eating the rainbows, among other things. Brook trout are technically not a trout, but a char. They’re a rarity and never get very big. None of these species are native. Rainbows are from the Pacific coast, brookies are from the Atlantic coast, and browns are from Europe. All are wild, meaning not stocked and naturally reproducing. One large rainbow that I see often has a strangely colored head — I suspect a genetic mosaic.

Three photos I took yesterday are a bald eagle (Haliaeetus leucocephalus), with very high probability Lucy, who has appeared in these pages before; a red-tailed hawk (Buteo jamaicensis); and another sandhill crane, probably a juvenile, showing off its wings.

As a lagniappe for the entomophiles, two midges (family Chironomidae) apparently copulating on the stripping skirt of my float tube. These are tiny.

 

 

Readers’ wildlife photos

September 6, 2019 • 7:45 am

Stephen Barnard has been busy fishing, but he favors us today with a new batch of photos from Idaho. His captions are indented.

The first four are rufous hummingbirds (Selasphorus rufus). They migrate through in August and put on quite a show at the feeders. They’re gone now.

Next is a moose (Alces alces) across the creek in early morning sun. I see this young bull frequently. He’s almost tame.

Next, a rainbow trout (Oncorhynchus mykiss) that I’m releasing.

Next, a woolly worm caterpillar on the handle of my fishing net. It surprised me. Beautiful creature up close — slow, exploratory, undulating motions. I don’t know anything about these other than what you can find on google. Apparently there are several species.

 

Next, a grasshopper on Loving Creek, taken while fishing. I’m in the habit of photographing insects that fish eat. Now they’re eating a lot of these. Again, I don’t know anything about these other what you can find on Google.

My d*g Deets has something of a following in WEIT. Here he’s recovering from hernia surgery, which was very successful, although manual, not robotic. I think the new style fabric cones in royal blue are fashionable.

Finally, just before sunrise over Loving Creek this morning. [This was yesterday.]

Readers’ wildlife photos

August 31, 2019 • 7:45 am

We have some underwater photos today, pictures taken by reader Peter Klaver. His descriptions are indented, and note that there are several of his movies linked to the text.

Last month two friends and I had a week of diving in the Red Sea. The underwater life there is simply stunning.

The highlight of the diving was seeing a pod of bottlenose dolphins, genus Tersiops (but I don’t know which species these were), passing close to our group. Below is a frame from a videoclip (76 MB mp4 movie) of them

Just after they had passed our group, they started getting very close to each other and making moves we didn’t understand very well. Once we were out of the water again, our dive guide told us they had been mating. So without us realizing it, we had dolphins mating right in front of us. Without the slightest bit of shame!

Other fish we saw weren’t as big, but some were more colorful.

A bluespotted ribbontail ray, Taeniura lymma. There is a videoclip (100 MB mp4) of it here.

A pufferfish; I don’t know the Latin name of the species.

Big turtles are always a welcome sight during a dive. They’re usually not shy, so unlike many fish they don’t flee the moment you try taking their picture.

No idea what these fish are.

A parrotfish:

The fish below has a mouth that looks slightly similar to the parrot fish above.

A moray eel. There is a videoclip (67 MB mp4) of another one here.

We saw shoals of fish, too. Here are moon fish:

And a really big shoal of which the picture below only shows a small part. A videoclip (77 MB mp4) shows the size of the entire shoal.

We went into a few old wrecks too. These can be full of shoals of often tiny fish too, as you can see in a videoclip here.

Readers’ wildlife photos

August 15, 2019 • 7:45 am

It’s been too long since we’ve had some photos by Stephen Barnard from Idaho, but he came through with this nice batch (and an explanation). His captions are indented.

I haven’t been doing much photography, for a variety of reasons, one of which is that I’ve been doing a lot of fishing.

This is my  pet fish, a  large, active, aggressive rainbow trout that dominates a deep pool. It’s a peculiar fish in that the right side of its head is dark compared to the rest of the body, which is unusually blonde. It’s striking. My theory, which is mine, is that it’s a genetic mosaic.

.

Pet fish taking a Trico spinner, a tiny mayfly that has died and fallen to the water. The fish gorge on these insects that hatch in multitudes.

.

Taking photos of fish is a problem. They’re usually the boring and repetitious “grip and grin” type photos. I typically fish alone and that makes it even more difficult. Hitch in the background likes to watch.

.

Instead, I’ve been photographing trout underwater at the time of release.

.
.
.
.
.

Some birds. These are barn swallows (Hirundo rustica). They build several nests every year under the eaves of my house and raise multiple broods. Kind of messy, but amusing. They keep the mosquitoes under control. The broods occupy the nests from time to time well after fledging, and I’ve noticed that they will eject newly hatched chicks to their deaths.

.

A black-chinned hummingbird (Archilochus alexandri) showing off his gorget.

.

A rufous hummingbird (Selasphorus rufus) spoiling for a fight.

.

The rare and endangered great-horned rufous hummingbird (Bubo rufus).

.

Deets (Canis lupus familiaris)

.