Category Archives: Insects, Fish, Frogs

Tracker Eggs May Save Endangered Turtles

Green sea turtle (photo from Wikimedia Commons)

Green sea turtles (Chelonia mydas, above) are endangered and olive ridley sea turtles (Lepidochelys olivacea, below) are vulnerable even though both have a wide distribution in the tropical oceans. The threats they face are caused by humans including boat strikes, nets, poaching of the adults and collecting their eggs.

Olive ridley sea turtles nesting in Mexico (photo from Wikimedia Commons)

Back in 2015 conservation scientist Kim Williams-Guillén came up with a way to protect turtle eggs by using GPS-equipped decoys. Her award-winning idea was tried recently in Costa Rica with the results published this month in Current Biology.

Green sea turtle laying eggs (photo from Wikimedia Commons)

A team of scientists led by Helen Pheasey placed a decoy egg in each of 101 clutches of green sea and olive ridley turtles. 25 of the clutches were stolen by poachers. Five of the GPS eggs were taken for a ride. One traveled 85 miles. This diagram from Current Biology shows the decoys and the routes they traveled.

Decoy eggs, data, and estimated routes used by turtle egg traffickers (illustration from Current Biology PDF. Click this caption for the full description)

Revealing the trade routes is a step toward saving the turtles though not the silver bullet. Conservation laws and their enforcement can be ambiguous from country to country. As Science Magazine explains:

Ultimately, though, scientists and nonprofits are going to need to engage communities with local outreach and education programs to save sea turtles, Williams-Guillén says. “The real meat and potatoes of conservation isn’t going to come from deploying eggs.”

Science Magazine — Endangered baby sea turtles may have new savior: GPS eggs

Every little bit helps. Fake eggs will allow more baby turtles to hatch and walk to the sea.

Baby green sea turtle (photo from Wikimedia Commons)

Read more in Current Biology Magazine: Using GPS-enabled decoy turtle eggs to track illegal trade.

(photos from Wikimedia Commons, diagram from Current Biology Magazine: Using GPS-enabled decoy turtle eggs to track illegal trade; click on the captions to see the originals)

Spiders On Caffeine

European garden spider on web (photo from Wikimedia Commons)

6 October 2020

Since I began blogging 13 years ago my morning life has settled into a predictable pattern: I get up very early (4:00 am), make coffee, settle at my computer and start writing. Coffee is essential.

What’s essential to me doesn’t work well for spiders. On caffeine they make wonky webs.

Effect of caffeine on spider web construction (images from Wikimedia Commons)

Why did a scientist bother to find this out? His friend wanted to sleep late.

Read the details in this vintage article, On Caffeine, written years ago when I got up later myself.

(images from Wikimedia Commons; click on the captions to see the originals)

Which One Is Mildly Poisonous?

Leopard frog and pickerel frog (photos from Wikimedia Commons)

22 September 2020

Pretty soon it’ll be too cold for frogs but right now we still have a chance to see these two in Pennsylvania. Though similar it’s useful to know the difference because one is mildly poisonous.

Northern leopard frogs (Lithobates pipiens), at left above, are harmless and sometimes green. Don’t rely on their green color for identification though because some are plain brown. All four below are northern leopard frogs from the same place in Minnesota. Notice that the spots on their backs are irregular circles and somewhat scattered even on the brown one.

Green morph (left) and brown morph (right) northern leopard frogs (photo from Wikimedia Commons)

Pickerel frogs (Lithobates palustris) are mildly poisonous. When frightened they excrete a poison from their skin that’s toxic to predators and mildly irritating to human skin. To identify them, notice the chocolate brown blob-like rectangles arranged in two rows between the two folds on their backs (dorsolateral folds).

Pickerel frog, Souderton, PA (photo from Wikimedia Commons)

The Pickerel frogs can also be distinguished by the bright yellow or yellow-orange color on the inside concealed surface of the thigh. Leopard frogs are white in the same area. 

BioKids article at Univ of Michigan

Here’s a live pickerel frog showing off his spots.

He’s the one that’s poisonous.

p.s. A note on Poisonous versus Venomous:

  • Poison is passive, just used as a defense. You have to ingest or touch a poisonous substance to be harmed by it.
  • Venom is active, injected into you by the animal that carries it. It’s used as both offense to capture prey and defense.

(photos from Wikimedia Commons, click on the images to see the originals)

Porcelain and Primrose

Porcelain berry, Three Rivers Heritage Trail, 7 Sep 2020 (photo by Kate St. John)

In September porcelain berry’s (Ampelopsis glandulosa) beautiful porcelain-like fruits show why the plant was imported as an ornamental.

Porcelainberry, 3 Rivers Heritage Trail in Pittsburgh, 7 Sep 2020 (photo by Kate St. John)

Unfortunately this Asian vine is terribly invasive, engulfing small trees and draping itself over large ones.

Porcelain berry drapes a hillside in Schenley Park (photo by Kate St. John)

Some people call it “wild grape” but you’ll never see grapes on it. Just porcelain berries.

This month you’ll find common evening primrose (Oenothera biennis) blooming in meadows, along roads and bike trails. The name implies that it opens only in the evening but I photographed these at midday. The flowers are 1-2 inches wide. The plants are hard to miss at six feet tall.

Common evening primrose, Eliza Furnace Trail, 7 Sept 2020 (photo by Kate St. John)
Common evening primrose buds, Eliza Furnace Trail, 7 Sept 2020 (photo by Kate St. John)

Meanwhile, bug love continues. This pair of goldenrod soldier beetles (also called Pennsylvania leatherwing (Chauliognathus pensylvanicus)) are perched on a flower in the Aster family while working to continue their species.

Spend time outdoors this week while the weather is good. Autumn is beautiful and all too short.

p.s. Thank you to Monica Miller and John English for correcting my bug identification mistake!

p.p.s. Did you notice that Pennsylvania is misspelled in the bug’s scientific name (only 1 ‘n’). This is not the only species with this misspelling. Can you name another?

(photos by Kate St. John)

Monarchs Are Using Their Sun Compasses

Monarch butterfly on swamp milkweed, Aug 2014 (photo by Steve Gosser)

10 September 2020

Though 2020 has been an awful year it has a silver lining: Monarch butterflies are relatively plentiful. I saw my first monarch in late July. Now that they’re migrating to Mexico I see several every day.

How are they navigating to Mexico?

During their fall migration, Eastern North American monarch butterflies (Danaus plexippus) use a time-compensated sun compass to aid navigation to their overwintering grounds in central Mexico.

Antennal circadian clocks in migratory monarch butterflies

The compasses are in their antennae! Combined with a circadian clock that figures out where the sun ought be at any time of day, the compass compensates for the sun’s position and keeps the monarch heading in a southwesterly direction.

Monarchs can navigate better than some of us!

On Throw Back Thursday, read more in this vintage article: The Sun Compass.

(photo by Steve Gosser)

p.s. The article was written seven years ago when the monarch population hit a dangerous record low. The population rebounded in 2018-2019 but it’s hard to know if they’re safe yet. This population graph from Journey North was not updated in spring 2020. I’ll bet COVID-19 interfered.

Bug Love and Galls

Bug love on boneset, 31 Aug 2020 (photo by Kate St. John)

5 September 2020

This week saw flurries of warblers migrating through Pennsylvania and a lot of bug love. The bugs were easy to photograph at Moraine State Park on 31 August.

Above, two insects are frozen in place as they mate on a boneset flower. I don’t know who they are. Do you?

Below, we were astonished to see large reddish galls on staghorn sumac leaves. These are woolly aphids called Melaphis rhois, one of the few whose eggs cause galls.

Melaphis rhois, staghorn sumac leaf galls, Moraine State Park, 31 Aug 2020 (photo by Kate St. John)

According to Wikipedia:

The galls occur when female aphids lay a single egg on the underside of the sumac leaf, inducing the leaf to form a sac over the egg.

There are so many galls on this sumac that they look like fruit.

Melaphis rhois, staghorn sumac leaf galls, Moraine State Park, 31 Aug 2020 (photo by Kate St. John)

It’s also called “red pouch gall.”

Melaphis rhois, staghorn sumac leaf galls a.k.a red pouch galls, Moraine State Park, 31 Aug 2020 (photo by Kate St. John)

My friend Melissa bravely opened a gall which scattered white powder everywhere. Woolly aphids!

Melaphis rhois — the inside of the gall, 31 Aug 2020 (photo by Kate St. John)

Inside the gall we easily saw larvae and a few adults.

Melaphis rhois inside their gall, 31 Aug 2020 (photo by Kate St. John)

How will they overwinter?

More bug love then next year’s galls.

(photos by Kate St. John)

Spelunking Inside A Frog

Dark-spotted frog (Pelophylax nigromaculatus) in Japan (photo from Wikimedia Commons)

28 August 2020

In case you missed it in early August, here’s amazing news from Kobe University about the way a beetle survives being eaten by a frog.

The frog is the dark-spotted frog in Japan (Pelophylax nigromaculatus), above.

The beetle is a water scavenger beetle, Regimbartia attenuata.

Water scavenger beetle, Regimbartia attenuata (photo from Kobe University)

When the frog eats the beetle, the beetle is (obviously) inside the frog’s digestive tract which resembles a long cave. Spelunca is Latin for cave.

The beetle actively crawls through the digestive tract to escape out the vent (anus) of the frog. Bugs that don’t keep moving don’t make it out alive.

Time required for the passage of Regimbartia attenuata and other beetles through the frog Pelophylax nigromaculatus from swallowing to excretion (credit: Kobe University)

Kobe University provided this movie to show what happens.

The word “scavenger” in the beetle’s common name may explain why he isn’t repulsed by what he’s crawling through as he goes spelunking inside the frog.

Read more about the study in this 4 Aug 2020 news release from Kobe University: An insect species can actively escape from the vents of predators via the digestive system.

(frog photo from Wikimedia Commons, all other media courtesy Kobe University via this news release)

Whirligigs

Whirligig beetles in Ohio (photo from Wikimedia Commons)

24 August 2020

This is the time of year to see whirligigs, those shiny water beetles that spin and swim on freshwater surfaces. They gather in large aggregations in late summer and fall and are hard to miss in August.

When you find an aggregation it may contain only one species or more than a dozen. With 700 species in the Gyrinidae family you have to be an expert to figure out who’s who.

Whirligigs swim on the surface, sometimes quite fast, or dive when threatened or to lay eggs.

They have amazing adaptations to fit their lifestyle:

  • Their compound eyes are divided into above-water and below-water halves which are able to see best in each environment. They watch for predators (insects, birds and fish) and prey (live or dead insects).
  • Their back legs are short paddles for swimming fast. Their front legs are long for grasping prey. The males’ front legs have suckers to hang onto females when they mate.
  • Whirligig beetles cannot walk but they can fly. Their wings carry them to other ponds when their own location dries up.
  • Adults need to breathe so they carry a bubble of air under their elytra when they dive. The bubble is positioned at the back end of the bug where their breathing parts are located.

See their breathing bubble in this PBS video about nature’s scuba divers:

(photo and image from Wikimedia Commons; click the caption to see the original. videos embedded from YouTube)

p.s. Just for laughs, here’s a whirligig that you can see at any time of year. 😉

Bugs At Work

Pollinators on green-headed coneflower, Moraine State Park 16 Aug 2020 (photo by Kate St. John)

22 August 2020

In late August the birds are silent but bugs are busy everywhere. Here are a few examples of recent bugs at work.

Above, pollinators visit green-headed coneflowers (Rudbeckia laciniata) at Moraine State Park.

Below, a midge laid its eggs on a flower head which grew into a huge gall. My guess at the midge’s identity is Asphondylia rudbeckiaeconspicua based on the description and photos posted here by The Michigan Nature Guy.

Large gall on green-headed coneflower, Moraine State Park 16 Aug 2020 (photo by Kate St. John)

Fall webworms are building webs and enclosing tree branches as they eat the leaves. The webs protect the caterpillars from predators and can become quite large, as shown below.

Fall webworms engulf a branch, Moraine State Park, 16 Aug 2020 (photo by Kate St. John)

The caterpillars won’t permanently damage the trees because the growing season is nearing its end.

Fall webworms surround a branch tip, Moraine State Park 16 Aug 2020 (photo by Kate St. John)

See a photo of the adult moth and read more about fall webworms here.

Fall webworms engulf a branch, Moraine State Park, 16 Aug 2020 (photo by Kate St. John)

Cicadas are still “singing” in Pittsburgh. Occasionally I find a molted exoskeleton like this one in Frick Park.

Cicada exoskeleton, Frick Park, 14 Aug 2020

And finally, at Duck Hollow I almost walked into a tiny caterpillar dangling from an invisible filament. The caterpillar blows in the wind, his filament touches another tree and he scrambles up. It’s an effective form of transportation. Much faster than walking.

Caterpillar descends on a filament, Duck Hollow, 8 Aug 2020 (photo by Kate St. John)

(photos by Kate St. John)

Surprising Enemies of Paper Wasps

Black-capped chickadee (photo from Wikimedia Commons)

21 August 2020:

The presence of European paper wasps (Polistes dominula) can be daunting until you realize they have enemies. Birds eat their larvae right out of the nest. Gerardine Baugh discovered this while watching a chickadee at a wasp’s nest outside her window.

Who knew that a chickadee would be so brave when confronted by a wasp?

p.s. If you missed it, learn more about European paper wasps in this week’s article.

And there’s good news from Ohio: When European paper wasps first arrived in Ohio they supplanted native paper wasps. Now that trend has reversed.

(photo from Wikimedia Commons; video by Geradine Baugh)