Insect Jamboree

Insects
Leaf-footed bug at Powdermill Nature Center, 19 August 2023 (photo by Kate St. John)

2 September 2023

Insect activity is pretty intense in late August and September as they run out of time to eat and mate before cold weather (usually) kills them.

While vegetarian insects, such as the leaf-footed bug above (Coreidae family), munch on fruits, nuts, plants and trees, the carnivores dine on insects. Carnivores include the migrating warblers who pick tiny bugs off of leaves and branches.

Every day predatory spiders weave a gauzy web on top of these Japanese yews in Shadyside, hoping for an unsuspecting insect.

Gauzy spider webs on Japanese yew, Shadyside Pittsburgh, 14 August 2023 (photo by Kate St. John)

Assassin bugs (Reduviidae family, nymph below) eat many insects in their lifetime.

Assassin bug nymph, Powdermill Nature Center, 19 August 2023 (photo by Kate St. John)

And if you want to red about a really creepy predator, check out this #bioPGH blog about The Super Spooky Sting of the great black wasp (Sphex pensylvanicus)

Meanwhile the vegetarian insectss are distracted by mating, as seen in this pair of Japanese beetles (Popillia japonica).

Japanese beetles mating while perched on tick trefoil amidst spreading dogbane, Sewickley Heights Park, 29 August 2023 (photo by Kate St. John)

Two flies were locked in some sort of embrace on my car yesterday morning at Schenley Park. Considering the size difference I wonder if this wasn’t fratricide.

Flies doing something on my car, maybe mating, Schenley Park, 1 Sept 2023 (photo by Kate St. John)

And in spotted lanternfly Lycorma delicatula) news: Yes the lanternflies are still quite present and they haven’t even begun to lay eggs yet. That’ll happen this month and next.

This week I found a milestone on the honeydew mold front: In Schenley Park on Friday I saw the white mold on top of sooty mold.

The whiteness in this photo appears to be the sun glinting off the Ailanthus tree trunk but in fact it’s white mold growing on top of sooty mold (black) on top of spotted lanternfly honeydew.

White mold on top of sooty mold on spotted lanternfly honeydew on an Ailanthus tree, Schenley Park, 1 Sept 2023 (photo by Kate St. John)

Ailanthus, “Tree of heaven,” is the host tree of the spotted lanternfly and they sure do love this one. Looking up, the tree is infested with lanternflies.

Spotted lanternflies coating an Ailanthus tree, Schenley Park, 1 Sept 2023 (photo by Kate St. John)

Expect more insect activity in the week ahead as bright sun and hot temperatures warm them up.

(photos by Kate St. John)

Out of Sight, But Not Out of Mind

Bird Behavior, Peregrines
Ecco and Carla bow at the nest, 31 August 2023, 4:17pm (photo from the National Aviary snapshot camera at Univ of Pittsburgh)

1 September 2023

The National Aviary’s streaming camera is off for the season so the Pitt peregrines are virtually out of sight, but they are not off my mind. Every day I check the Cathedral of Learning’s ledges to see where they’re perched and I look at the snapshot camera in case they’ve been to the nest.

Activity at the nest picked up this week because fall is coming and migration is underway. The length of day is similar to spring and they’re taking an interest in songbird migration as prey flies overhead at night.

Ecco and Carla bowed at the nest three times yesterday, including an extended bowing session, to strengthen their pair bond and their claim on the nest.

All of Pitt’s resident peregrines(*) stay home for the winter and I expect Ecco and Carla to do the same. They don’t need to migrate because there’s plenty of food in the winter (pigeons and starlings) and their “cliff” is too valuable to lose by vacating it for six months.

So I’m still watching. The Pitt peregrines may be out of sight but they are not out of my mind.

(*) There’s a lot of history that allows me to say that. Peregrines have lived at the Cathedral of Learning for 22 years, spanning 8 adult birds.

(photos from the National Aviary snapshot camera at Univ of Pittsburgh)

Sleeping On Migration

Bird Behavior, Migration
Sparrow asleep in New Mexico (photo by Larry Lamsa via Flickr Creative Commons license)

31 August 2023

Migration is exhausting work and since warblers migrate at night, they must rest and refuel during the day. Food and good cover are both essential at their rest stops. Sleeping is a dangerous activity where predators lurk.

A study published in Current Biology, August 2019, revealed one way that migrating warblers manage these dangers and demands: They adjust their sleep postures depending on their physical condition and physiological needs. Plump, well-muscled birds tend to sleep with their heads held upright, while scrawnier warblers tuck their heads into their feathers, a posture that makes them more vulnerable to predation but helps them conserve their much needed energy.

— New York Times: Some Migratory Birds Sleep Better Than Others, August 2019

Fit warblers can afford to be vigilant. They puff up and sleep in a watchful posture, sometimes out in the open. This makes them ready to escape at a moment’s notice.

Sardinian warbler asleep on a branch (photo from Wikimedia Commons)

Exhausted warblers hide in thickets and tuck their heads under their wings. This provides much needed rest and protects against heat loss but makes them vulnerable to predators. Interestingly, these same birds sleep less than those in good condition because they have to spend more time foraging.

Bird sleeping with head tucked under wing (photo from Wikimedia Commons)

Some long distance migrants, such as the ocean-going great frigatebird, can sleep in flight.

Great frigatebird in flight (photo from Wikimedia Commons)

A 2016 study equipped great frigatebirds (Fregata minor) with EEG equipment and proved that they sleep while flying though they get less sleep in the air than on land. Read more in this vintage article.

Asleep In Flight

It would be nice to safely sleep while doing other things. Yawn! I’m ready right now.

(photos from Wikimedia Commons, see links in the captions)

The Calm Before The Crows

Crows & Ravens, Vocalizations
Fish crows at Red Hook, NY (photo from Wikimedia Commons)

30 August 2023

In August in the East End of Pittsburgh we get a taste of November dusk. It isn’t the weather or the clouds or the time of sunset. It’s a flock of more than 100 crows, a hint of the thousands to come this fall, that gather on rooftops along Neville Street before flying west to roost.

This year in early August the crows were absolutely silent but as the month progressed a few spoke out, telling me they were in a mixed flock of American and fish crows. American crows (Corvus brachyrhyncos) say “Caw.” Fish crows say a nasal “Uh-oh” (Corvus ossifragus). It’s the only reliable way to tell them apart.

American crow: “Caw Caw Caw.”

Fish Crow: Nasal “Uh oh”

video by Sayre Nature HD on YouTube

I wanted to count by species but the crows remained silent and unidentifiable through most of the month. I tried to tell them apart by sight but my focus on appearance made it impossible to count. So I stop trying. My August eBird checklists place all of them as “American crows” with an X for “Fish crows present.”

Then suddenly last Saturday they were all “talking” and about three quarters of them were fish crows. The flock continued on Sunday evening but I was too busy to count. I shouldn’t have assumed they’d be here on Monday. They were gone and they haven’t been back.

The big flocks will arrive in late October, comprised of 90+% American crows.

For now we’re in the Calm Before The Crows.

p.s. eBird’s Fish Crow Weekly Abundance map shows a dot in Pittsburgh in the month of August … and then it’s gone. Watch the animation here.

(credits are in the captions)

Olive-Sided Flycatchers Stop to Refuel

Migration
Olive-sided flycatcher (photo from Wikimedia Commons)

29 August 2023

Olive-sided flycatchers (Contopus cooperi) are rare birds in Pittsburgh. Not only have they declined 78% since 1970, but they are only present on migration and then just one or two per season. When three individuals were found on the same day, Friday 25 August, in Allegheny County it was rare indeed. These three were not the same bird:

  • Sewickley Heights Borough Park at 8:20am, seen recently on Monday 28 Aug
  • Hartwood Acres, Saxonburg Fields at 10:50am
  • Homewood Cemetery at noon

Though olive-sided flycatchers nest from Alaska to Newfoundland and southward into the Cascades and Rockies, not much is known of their migration routes. In the fall the eastern birds generally flow westward within Canada, then hang a left at Minnesota and migrate through the Great Plains and eastern Rockies. You can see their relative abundance from the 3rd week of August through the 3rd week of October in this slide show.

Olive-sided flycatcher weekly relative abundance from eBird Status and Trends

Alaska’s breeding olive-sided flycatchers are declining rapidly and have one of the longest migrations of any flycatcher — from Alaska to Peru. Migratory stopover sites are very important for their survival but nobody knew where they went so a study team, headed by Julie C. Hagelin, decided to track the birds’ migration by catching them in mist nets and attaching geolocator backpacks.

What they discovered when the birds returned is that Alaskan breeders fan out across the Rockies on their way south, some as far east as Texas, before they head through Mexico to South America. They also found 13 important stopover sites that are critical to the birds’ survival on migration. Their favorite spots are slightly different in Central America in fall versus spring. Two of the 13 sites are in the U.S. Cascade Mountains. All the sites are on these maps.

(illustration from DeGruyter: Revealing migratory path, important stopovers
and non-breeding areas of a boreal songbird in
steep decline)

Pittsburgh never figures heavily in the olive-sided flycatcher’s travel agenda though this year we seemed to be an attractive stopover. Our birds probably come from breeding sites in eastern Canada.

Are our olive-sided flycatchers stopping at the same places in Central America as the Alaskan group? We won’t know until some runs a similar study in eastern Canada.

(photo from Wikimedia Commons, abundance maps from eBird, stopover maps from DeGruyter; origin links are in the captions)

Yesterday at Schenley Park on 8/27

Books & Events, Insects, Plants & Fungi
Schenley Park outing, 27 August 2023 (photo by Kate St. John)

28 August 2023

Yesterday turned into a nice day, but when eight of us met at Schenley Park at 8:30am the temperature was cool with low clouds and the sky was blank gray. Normally the birds would have slept in but the migrants were hungry. We found 22 species.

Best Bird is hard to choose. Was it the belted kingfisher that hunted over Panther Hollow Lake? The ruby-throated hummingbirds that floated among the trees? Or the warblers — Blackburnian, magnolia and chestnut-sided?

Between birds the bugs took center stage. Milkweed bugs swarmed on swamp milkweed pods …

Milkweed bugs on swamp milkweed seed pods, Schenley, 27 August 2023 (photo by Kate St. John)

… and spotted lanternflies sipped on the Ailanthus trees that inspired my blog about sooty mold on honeydew. I was curious: Did the rain wash away the sooty mold? No.

Spotted lanternfly honeydew below an Ailanthus tree is black with sooty mold, Schenley Park, 27 Aug 2023 (photo by Kate St. John)

Fourteen Canada geese flew over to join the 70 already grazing on Flagstaff Hill. Geese were absent from Flagstaff Hill this summer while they molted their wings feathers and did not return in large numbers until early August.

Here’s our eBird checklist: Schenley Park, Allegheny, Pennsylvania, Aug 27, 2022 8:30A – 10:30A

Canada Goose (Branta canadensis) 14
Rock Pigeon (Feral Pigeon) (Columba livia (Feral Pigeon)) 2
Mourning Dove (Zenaida macroura) 9
Ruby-throated Hummingbird (Archilochus colubris) 2
Belted Kingfisher (Megaceryle alcyon) 1
Red-bellied Woodpecker (Melanerpes carolinus) 2
Downy Woodpecker (Dryobates pubescens) 5
Northern Flicker (Colaptes auratus) 2
Blue Jay (Cyanocitta cristata) 5
Carolina Chickadee (Poecile carolinensis) 8
Tufted Titmouse (Baeolophus bicolor) 7
White-breasted Nuthatch (Sitta carolinensis) 2
Carolina Wren (Thryothorus ludovicianus) 3
Gray Catbird (Dumetella carolinensis) 1
American Robin (Turdus migratorius) 4
House Finch (Haemorhous mexicanus) 3
Chipping Sparrow (Spizella passerina) 15
Song Sparrow (Melospiza melodia) 1
Magnolia Warbler (Setophaga magnolia) 3
Blackburnian Warbler (Setophaga fusca) 2
Chestnut-sided Warbler (Setophaga pensylvanica) 2
Northern Cardinal (Cardinalis cardinalis) 6

The next outing will be 24 September at 8:30a in Schenley Park at Bartlett Playground.

(photos by Kate St. John)

Why Leaves Turn Black Under Tree of Heaven

Insects, Spotted Lanternflies, Trees
Spotted lanternfly honeydew below ailanthus tree turns black with sooty mold, Schenley, 25 Aug 2023 (photo by Kate St. John)

27 August 2023

In Schenley Park’s Panther Hollow there are only a handful of Ailanthus altissima trees (Tree of Heaven) which I rarely paid attention to until recently. A couple of weeks ago I noticed that the plants and ground beneath those trees were wet, though it had not rained. This week the leaves and ground are black. Both phenomena are a by-product of the spotted lanternfly (Lycorma delicatula) invasion.

Spotted lanternflies on a tree trunk, one egg mass below them (photo by Emelie Swackhamer, Penn State University, Bugwood.org)

Spotted lanternflies (Lycorma delicatula) are sucking insects that pierce the bark of their host plant, Ailanthus, and sip the sugary phloem that travels from the leaves to the rest of the plant. (Phloem flow is orange in the diagram below.)

Flow of xylem and phloem in plants (image from Wikimedia Commons)

Everything that eats excretes and spotted lanternflies are no exception. Their watery “poop” is called honeydew because it is full of sugar.

video embedded from Bug of the Week on Youtube

If there were only a few lanternflies we would never notice the honeydew but when a large number coat a tree the honeydew is hard to miss, especially for the consumers of honeydew: bees, wasps, hornets, ants and butterflies.

Butterfly sips on spotted lanternfly honeydew (photo by Rebekah D. Wallace, University of Georgia, Bugwood.org)
European hornet sips lanternfly honeydew (photo by Rebekah D. Wallace, University of Georgia, Bugwood.org)

Sugary honeydew eventually grows sooty mold. Everything with honeydew on it turns black.

Sooty mold is a fungus that appears as a black, sooty growth on leaves, branches and, sometimes, fruits. It is non-parasitic and not particularly harmful to plants apart from being unsightly. Potentially, it could affect the plant’s ability to use the sun for photosynthesis. If you can rub the black growth off with your fingers, it is probably sooty mold. If you cannot rub it off, it is most likely something else.

— Univ of Hawaii Master Gardener Program: FAQ, Sooty mold
Sooty mold on vegetation beneath Ailanthus tree (photo by Richard Gardner, Bugwood.org), yellow circle added
Spotted lanternfly honeydew below ailanthus tree turned black with sooty mold, Schenley, 25 Aug 2023 (photo by Kate St. John)

Eventually white mold may cover the honeydew. I haven’t seen this yet but I’m watching for it.

Spotted lanternfly honeydew grows mold (photo by Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org)

Will we ever be free of spotted lanternflies? Yes! Check out this blog This, Too, Shall Pass.

(photo credits are in the captions with links to the originals)

Seen This Week: Jewelweed and Lobelia

Phenology, Plants & Fungi
Orange jewelweed, Beechwood Nature Center, 16 August 2023 (photo by Kate St. John)

26 August 2023

Well, mostly “this week.” Two photos are older but I didn’t have room for them last time. Here’s a selection spanning 12 days.

  • Orange jewelweed (Impatiens capensis), above, does well at ASWP’s Beechwood Nature Center but is nearly extirpated from Schenley Park by deer overbrowse.
  • Tiny pink and white flowers of willow-herb (Epilobium sp) at West Penn Park on Polish Hill.
  • Sneezeweed at ASWP’s Beechwood Nature Center. They’ve cultivated many native flowers in the meadows.
  • Porcelain berry leaves have many shapes, even on the same plant. A photo of four shapes.
  • Great lobelia at ASWP’s Beechwood Nature Center.
  • Pink-orange sunrise on 24 August.
Willow-herb, West Penn Park, Polish Hill, 20 August 2023 (photo by Kate St. John)
Common sneezeweed (Helenium autumnale), Beechwood Nature Center, 24 August 2023 (photo by Kate St. John)
4 shapes of porcelain berry leaves, Nine Mile Run Trail, Lower Frick, 13 August 2023 (photo by Kate St. John)
Great lobelia, Beechwood Nature Center, 24 August 2023 (photo by Kate St. John)
Sunrise in Pittsburgh, 24 August 2023 (photo by Kate St. John)

(photos by Kate St. John)

Peregrine Family Life in August

Bird Behavior, Peregrines
“Mother and son on the ledge right now” 17 July 2023 (tweeted by @FaBPeregrines)

25 August 2023

Because the Pitt peregrines had no eggs this year I miss seeing their young on camera. To fill that gap I’ve been following the Fulham and Barnes Peregrines at Charing Cross Hospital in London, UK whose daily lives are chronicled by @FaBPeregrines.

Azina, Tom and their son P6T (named for his band number) are frequently seen on camera, even in late August. P6T’s dispersal from his natal site is on a later schedule than we’re used to in Pittsburgh.

Juvenile peregrines in Pittsburgh fledge in early June and leave in July. At Fulham and Barnes, P6T fledged in the fourth week of May and is still hanging around in late August. His persistence gives us an opportunity to watch a peregrine family in late summer when the youngster hunts on his own.

Notice how the ledge is cluttered with prey on 23 August compared how clean it was on 17 July, at top . Someone has been messy. 😉

Follow this peregrine family @FaBPeregrines on X, formerly known as Twitter.

(tweeted by @FaBPeregrines)

This, Too, Shall Pass

Insects, Spotted Lanternflies
Spotted lanternflies land to roost just before sunset, Pittsburgh, 22 August 2023 (photo by Kate St. John)

24 August 2023

Spotted lanternflies (Lycorma delicatula) are everywhere in the East End of Pittsburgh and along our rivers and railroads. One even triggered a snapshot on the motion detection camera at the Pitt peregrine nest. Aaarrg!

Spotted lanternfly perched on the National Aviary snapshot falconcam at Univ of Pittsburgh

Right now, while the invasion is getting worse by the day, it is hard to imagine a time without them but that day will come. The bugs have daily, seasonal and annual cycles and their population trend goes down, based on what happened in eastern PA where they were first detected. Let’s take a look.

Daily dispersal, nightly roost. During the day adult lanternflies disperse to the sky but at dusk they land on buildings and trees to “roost” overnight. Dusk is an unpleasant time of day as they aggregate near us but it’s a good opportunity to catch them with a water bottle (video shows how). [Put a lid on the bottle and the bottle in the freezer. They die in the cold.]

Seasonal disappearance of adults in late fall. Spotted lanternfly adults mate and lay eggs in late summer and fall. Winged adults started to appear in July in Pittsburgh but they did not reach a crescendo until mid-August. They’ll be present in September and October and completely die off at the first frost. I expect their presence to taper before they disappear.

I have not been able to find out if the individuals die shortly after mating and laying eggs but if so the population would taper quickly. I’ll know more in November.

Invasion lasts two to three years based on experience in Eastern PA.

Lanternflies were a plague in Berks County(*) in 2018 and 2019 but by 2021 they were hard to find. That year the Reading Eagle wrote “Where have all the spotted lanternflies gone?“

Similarly the bugs plagued Philadelphia in 2020 but reports went down 95% in 2022 and this month the Philadelphia Inquirer asks Should we still care about spotted lanternflies in 2023? and What should you do if you see spotted lanternflies?

Notice that Philadelphia is saying “IF you see spotted lanternflies,” not “WHEN you see spotted lanternflies!”

Based on these reports I’d say the infestation lasts two to three years and then drops to an unremarkable level. It seems to be a bell curve.

Spotted lanternfly invasion appears to be a bell curve with maximum at 2-3 years (guesstimate by Kate St. John)

The Pittsburgh area has had spotted lanternflies since 2020. This summer we are in the first plague year (Year label 5). Next summer will be bad, too, but by 2025 or 2026 they’ll be virtually gone.

This, too, shall pass.

p.s. Great News! Two naturally occurring native fungi infect and kill spotted lanternflies in great numbers. Batkoa major and Beauveria bassiana decimated the spotted lanternfly (Lycorma delicatula) populations near Reading, Pennsylvania in 2019. Fingers crossed!

(*) Berks County in 2014 is the location where spotted lanternflies were first identified in the U.S.

(photo by Kate St. John and from the National Aviary snapshot camera at Univ. of Pittsburgh, graph by Kate St. John)