The guys are back in the field with our good friend Dr. Jason Dombroskie from the Cornell University Insect Collection!
Listen in as Jason leads us through fields and forests, trusty butterfly net in hand, filling us in on the so-called “Insect Apocalypse.” Are insect populations really collapsing worldwide? What do the numbers say? How bad is it, and — most importantly — what can we do about it?
In this part, we head out on the trail with Jason. He introduces us to some insects we find along the way and schools us on why insects are so important, and in part two – he delves into the details of the insect apocalypse – what we know and what we don’t know.
And since we feel bad that you can’t see what we got to see – we bring back a little trick we had in our last episodes with Jason – each time we find a critter listen for the sound of a camera shutter. That’s the signal to visit this episode’s page on our website – thefieldguidespodcast.com - we’ll have photos there timestamped so you can see what we’re looking at, along with some extra info. Enjoy…
This episode was recorded on August 21, 2025 at Rattlesnake Hill Wildlife Management Area in Dalton, NY..
Episode Notes
Steve said he heard that there are more species of just weevils than there are of fish. Is that true? At one point in the episode Steve mentioned he’d heard there are more species of weevils than there are of fish. I looked it up, and he’s right! Scientists have described around 60–70,000 weevil species, with the real total likely over 100,000, while all the fish in the world come in at about 35,000 species. So as surprising as it sounds, Steve’s claim checks out—the humble weevil family really does outnumber all the fish.
It was also mentioned that some insects are only known from a single specimen in a collection and have never been seen again in the wild. We looked for a study and found a large one from 2018 that looked at more than 800,000 insect species – it found that about one in five—around 19%—are described from a single specimen and never collected again (Lim et al., Current Biology, 2018). It really shows how much of insect diversity is still barely known.
Pollard Walk - During the episode Bill asked about something called a Pollard Walk. That’s actually a standard insect survey method. The idea is simple: you walk a fixed route—usually the same path each time—at a steady pace and record every insect you see within a certain distance, often about 2.5 meters on each side. It’s kind of like a birding “point count,” but moving. The method, named after Eric Pollard who developed it in the 1970s for butterfly monitoring, is still one of the most widely used ways scientists track insect populations over time.
Bat Lake Trail Guide Picture: Jason mentioned the picture from Algonquin Provincial Park’s Trail Guide to their Bat Lake Trail. The picture showed animals with a size that corresponded to their biomass in the ecosystem.
Episode Links
The Cornell University Insect Collection
Also, check out their great Instagram feed
And their annual October event Insectapalooza
Find out more about the recently discovered species of Swallowtail, Papilio solstitius, commonly known as the Midsummer Tiger Swallowtail- https://www.sci.news/biology/papilio-solstitius-13710.html
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Photos by timestamp
10:56 – A type of Snout Moth – the Vagabond Crambus (Agriphila vulgivagellus)
Attribution:Observation © Gabe King · some rights reserved - https://www.inaturalist.org/observations/317284737
Attribution: Observation © Owen Carson · some rights reserved https://www.inaturalist.org/observations/317150510
30:51 The round, circular galls found on the leaves of goldenrod plants, caused by the Ambrosia Gall Midge, Asteromyia carbonifera, and a symbiotic fungus. This relationship is unique among gall-making insects because the gall's formation is directed by the fungus, not the midge larva itself.
32:37 The Divided Olethreutes moth (Olethreutes bipartitana) is a small leaf-roller moth within the family Tortricidae and genus Olethreutes. This tiny moth, typically measuring 6-10 mm in length, features black, white, and gray colors with two white bands on its rolled wings and is known for its "bird poop mimicry" to avoid predators.
Attribution: public domaiun https://www.inaturalist.org/observations/299481875
48:05 Formica ants tending treehoppers is a mutualistic relationship where the ants protect the treehoppers and their eggs from predators like jumping spiders in exchange for the treehoppers' sugary, nutrient-rich honeydew. This classic symbiosis involves the ants "milking" the treehoppers, moving them around, and aggressively defending their "herd". In return for the ants' protection and care, the treehoppers' survival rate increases significantly, leading to a beneficial outcome for both species.
49:15 Spittlebugs - The superfamily Cercopoidea, some members of which are called froghoppers and still others known as spittlebugs, are a group of hemipteran insects in the suborder Auchenorrhyncha. Wikipedia
Attribution© Nikolai Vladimirov / some rights reserved / https://www.inaturalist.org/photos/12164443
Attribution: public domain / https://www.inaturalist.org/observations/240214944
50:23 The leaf miner that commonly feeds on goldenrod plants is Cremastobombycia solidaginis, a moth in the Gracillariidae family, also known as the Goldenrod Leaf Miner moth. This species creates distinctive mines or tunnels within the leaves of various goldenrod plants as it grows.
50:58 Casebearer moths are Lepidoptera larvae known for creating portable silk cases for protection and camouflage, with some species like the household casebearer feeding on hair and fibers indoors, while others attack foliage. The larvae of the household casebearer (Phereoeca uterella), also called a plaster bagworm, form flat, oval cases from silk, sand, and debris, feeding on things like hair and spider webs. Other casebearers, in the family Coleophoridae, feed on leaves, twigs, and fruits and often overwinter in their cases.
Attribution: Public domain: https://www.inaturalist.org/observations/314479236
Attribution: Observation © Shumik A · some rights reserved / https://www.inaturalist.org/observations/317352408
55:01 The Diamondback Moth (Plutella xylostella) is a globally distributed pest known for the immense damage its larvae cause to cruciferous crops like cabbage, broccoli, and kale. Its name comes from the diamond-shaped markings on the adult moth's back.
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