• So Many Butterflies… Go FIGure

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    ‘Tis the season… a little later than usual, but the season nonetheless. While I was camping in New England, the figs on the trees outside my garden decided to start ripening in my absence. By the time I returned this past week, they were fully ripe, which had not gone unnoticed by many of my woodland neighbors.

    As in past summers there is a bit of a race to see who gets to the ripe figs first. I tend go out each morning and pick those figs that are starting to ripen before they fall prey to the other local fig-eaters. In the past it’s been the usual suspects… Hornets, Yellow-jackets, June beetles, and a few species of birds – especially woodpeckers and crows. But the trees were full of overripe figs when I returned and the table had been set for everyone. Now there are fruit flies, hornets, birds, and butterflies all over the fig trees.

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    Ripe fig with fruit flies (click on photos to enlarge)

    Many types of butterflies do not live on nectar alone – some species prefer overripe fruit, tree sap, and even decaying animals or scat (animal poop) to feed on. Decaying fruits have carbohydrates and minerals, necessary to most butterflies. Butterflies have excellent chemo-receptors and are able to locate sources of food like rotting fruit from great distances.

    Butterflies feeding on fig
    Butterflies feeding on fig dropped on fence post by a bird

    These figs must have the right sensory signals as I was amazed at the number and variety of species attracted to the fig feast.

    Red-spotted Purple on fence post
    Red-spotted Purple showing underside of wings

    The most noticeable of the scaly-winged fig-feeders are the Red-spotted Purple butterflies. They are common here in the Piedmont and are easily recognized by the red-orange spots on the undersides and the bright iridescence on the upper surface of their wings. I rarely see them nectar at flowers but often find them on tree sap, bird droppings, and rotten fruit.

    Red-spotted Purple spread wing
    Red-spotted Purple basking

    Yesterday afternoon there were over a dozen of these beauties flitting around the fig trees. With so many around, it should be a good year for finding their highly sculpted eggs at the tips of Black Cherry leaves, an abundant tree along the power line.

    Carolina Satyr
    Carolina Satyr

    Another abundant butterfly on the figs is much less noticeable – the diminutive Carolina Satyr. There may actually be even more of these flying around than the Red-spotted Purples, but they have an erratic, lilting flight and when they land, they can be tough to see.

    Carolina Satyr top view
    Carolina Satyr top view

    The undersides have a few noticeable eye spots but the upper wings are more moth-like and drab than most species of butterfly. Since they tend to be low-flying, they are often overlooked in the garden. I have yet to find one of their eggs or a caterpillar, which feed on various species of grasses. Guess I will just need to spend a little more time observing since there are now so many out and about.

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    Eastern Comma feeding on fig

    The Eastern Comma is a quick and erratic flyer that is fond of fruit, tree sap, and carrion. One of the so-called Anglewings (named for their sculpted wing edges), it can be separated from its close cousin, the Question Mark, by looking at the silvery marking on the underside of the hind wings. You can see the curved punctuation mark clearly in this photo and also see that it lacks the small dot on the distal end of the mark, so this is an Eastern Comma.

    Comma feeding on fig
    Eastern Coma showing bright orange upper surface

    When they flash open their wings, they are a beautiful brownish orange with dark spots. This is one of the few NC species of butterflies that overwinters as an adult.

    Tawny Emperor
    Tawny Emperor

    My favorite fig-feeder is one I rarely see elsewhere – the Tawny Emperor. Very similar to the more common Hackberry Emperor, both species share the restrictive habitat needs of an area with Hackberry or Sugarberry trees for host plants. Both species also share the unusual habit of often landing on sweaty human observers to probe for salt. As hot as it is supposed to be today, maybe I will go out and sit near the fig trees and see if I can attract a few. The things we do for science:)

  • Looking for Leviathan

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    Many years ago I had the privilege of co-leading a week-long whale watching workshop aboard a schooner in Maine for the North Carolina Museum of Natural Sciences. It was an experience I will never forget (for many reasons). So, while traveling up the coast of Maine I was looking for opportunities to see whales again. There is a well-known whale watch company in Bar Harbor that cruises many miles offshore in a large, fast catamaran. They have a good success record, but it looked like it might be so crowded that it would not be my cup of tea.

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    When I found out about a smaller company out of Eastport, Maine, that took smaller groups out for whale watching, I jumped at the chance. Coastal towns like Lubec and Eastport are a far cry from the hustle and bustle of touristy Bar Harbor. This is what Maine is really all about. It was a dreary morning and when I went in to pay for the trip I was very pleased to see the company name, Eastport Windjammers. Looking across the street to the dock I could see a beautiful old wooden schooner, the Ada C. Lore. Originally built in 1923, this 118 foot beauty was used to dredge oysters under sail. She is one of only three remaining historic Chesapeake Bay oyster schooners in the United States.
    The weather had reduced the number of willing passengers to only 10, barely enough to make a go of the trip. Once the captain and crew arrived we were off.

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    There were a number of birds we passed as we cruised out toward the bay – Bonaparte’s Gulls, Black Guillemots, and a couple of Razorbills. As we neared the shore of an island, the Bald Eagles began to appear. First only a couple, then many, all flying and calling in the gray sky. Every now and then, an Osprey would swoop down and harass one of the larger birds. One of the deckhands said that toward the end of August eagle numbers would jump dramatically as schools of fish moved into the bay. That is also the time when the most whales are nearshore, including the Humpbacks. The deckhand referred to Humpbacks as the rock star whales because of their tendency to put on quite a show for visitors.

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    Within a few minutes we encountered our first Minke Whale. The Minke (pronounced “mink-ee”) Whale, is a small, streamlined baleen whale found in most of the world’s oceans. They can reach lengths up to 33 feet and weigh up to 10 tons. Minke Whales are one of the most commonly seen baleen whales along the Maine coast. This area is an important feeding ground for whales, who go there to take advantage of the rich amounts of schooling fish, plankton and krill during the warmer months.

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    The dorsal fin of the Minke is tall and curved, and is located two-thirds of the way back on the body. That is usually about all you get to see when a Minke breaks the surface. They have a small blow, and usually do not extend the flipper, tail or much of their body above the surface, and rarely breach like Humpbacks.

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    Soon there were several Mlinkes around the ship. And they were close. One whale in particular was swimming all around our vessel. It was distinctive in that it was missing most of its dorsal fin. The deckhand called it Stumpy and it was well-known to this ships’ crew.

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    On one close approach, Stumpy raised up out of the water a little more than usual. My photo shows a series of whitish marks on Stumpy’s body at the waterline. I initially thought they were some sort of ectoparasite but looking online it appears as though these are scars on the whales’ skin left by feeding Lampreys. Lampreys feed by attaching themselves to the skin of fish and marine mammals, rasping through the skin and sucking out blood. If these are indeed Lamprey feeding scars, Stumpy has apparently fed quite a few.

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    After spending over an hour with the whales, we headed back to port. Along the way we were treated to a large group of seals laying out on some exposed rock. There are both Gray and Harbor Seals in this area, but most of these appeared to be the latter.

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    Harbor Seals grow to about 5-6 feet in length, and weigh between 200-300 pounds. They can be quite variable in color ranging from light brown to dark gray, with light undersides. They also may have scattered light and dark spots.

    A Harbor Seal in the water looks a bit like a dog, with its round head, long whiskers and large eyes peeking above the water surface. This is the species we most often see on the North Carolina coast. The short cruise brought back a lot of good memories and increased my desire to spend more time in the future looking for marine mammals.

  • Faces in the Forest

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    In every walk with nature one receives far more than he seeks.
    John Muir

    I find great peace in a walk in the woods. And I usually find something that causes me to pause and look closer. I appreciate these simple moments of time and reflection and know I am lucky to have the opportunity to be a woods watcher, especially when the woods are like those I have walked in this past week.

    Sometimes you find things that you either don’t expect or that fire some neurons in an unexpected way. I had two such moments in recent walks.

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    On a quick stroll at Quoddy Head State Park I saw this mushroom staring up at me. It isn’t often I frown in the woods so I was a bit taken aback by the gloomy glare of this fungus. A quick snap with the iPhone and I moved on, wishing the next critter to take a bite would result in an attitude adjustment.

    The next trail side countenance was a bit more surprising. The rain had just stopped when I strolled down a path in New Hampshire and came upon a puddle. I remembered a striking photo a friend had taken of water droplets in a woodland pool so I stopped to give it a try.

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    The first few pictures yielded nothing special or no drip pattern at all. Then I looked closely at the last image on my phone and it made me smile.

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    I am usually happiest when I am in such places but it is a bit rare when the feeling seems so mutual. And for the record, this image is real with no adjustments other than a slight crop.

  • A New Day in New Hampshire

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    After a day of driving through torrential rains I reached a beautiful Forest Service campground in White Mountain National Forest in New Hampshire. A few of the campsites had standing water but mine was mainly dry. I could hear the roaring waters of a creek downslope from me as the rain subsided. And then, as if on cue, it stopped and a patch of blue sky appeared. Time to set up camp!

    The sounds of the creek soon beckoned and I hiked down to take a look at what a few inches of rain does to a mountain stream.

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    The water rushed over and between boulders – a sound that would make for good sleeping.

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    The trail back to the campsite was full of details to be taken in – fungi, patterns on the bark of white birch trunks, tree shadows on a boulder…my only wish is that I was staying longer than one night.
    These north woods are special. I will return.

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  • Mainely Beautiful

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    I am winding down my camping trip to the north woods and the Maine coast. It has been a glorious week of hiking, camping in almost perfect campsites, and taking in the sights of a stunningly beautiful part of our country. Unlike many of my other outings, this one turned out to be less about wildlife and more about soaking in the essence of the place – the light over the ocean at sunset, the rhythmic sloshing of the waves on pink granite boulders, and the quiet of the fragrant north woods.

    And in what must be a first for me, I rarely took out the big lenses, much less the 7D. This is my first trip that I documented mainly with my iPhone…go figure. The relative lack of wildlife and the amount of hiking made it much easier to just carry the camera in my pocket.

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    Highlights of the trip include hiking in Acadia, especially up and over the Bee Hive by climbing a steep trail with steel ladders on the rock face, quiet breakfasts on secluded rock beaches, and the delicate beauty that surrounds you as you wander the rocky coast and the north woods. The temperatures, scenery, and forest made me think of the Maine Coast as being like an ocean on the slopes of my home states’ tallest mountain, Mount Mitchell. A great combination, to be sure.

    Cellular service has been, and remains, elusive, so I will simply post a few
    memories of the week. I hope to return soon.

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  • A Tale of Two Spiders

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    A friend found this orb spider in the driveway last week. She noticed something wasn’t quite right and called me over.

    Orb Spider
    Orb Spider

    At first glance, the spider looked like it was wearing a white belt. A closer look and I could make out that it wasn’t an arachnid fashion accessory but rather something much more sinister – a grub, most likely a parasitic grub of some sort.

    Orb Spider with parasitic grub 1
    Orb Spider with parasitic grub

    I have seen a parasitic grub on a spider once before but it was much smaller and was on top of the spider’s abdomen instead of hugging the spider’s “waist” as in this case. After taking a few pictures I released the very active spider on the railing of the deck.

    Parasitic Wasp captured by spider 2
    Parasitic wasp grub on spider

    I went in and searched the web for parasitic grubs on spiders and quickly found information which made me believe this is a wasp grub. One reference said the grub clings to the juncture of the spider’s two body parts as this is a place that the spider cannot reach. After reading this I decided to keep a watch on the spider (it remained near the deck railing overnight) for a few days and see what happened.

    Parasitic grub
    Parasitic grub in web

    The next day when I checked on the spider I was amazed to see the grub dangling in a loose web, but no spider. The grub had grown significantly overnight. I went in for the camera and came back out to photograph the grub (Canon 7D, 100mm Macro with extension tube, and Canon MT-24EX Macro Twin Lite flash). It was wriggling and as I watched I could see it was beginning to spin a cocoon in the loose webbing. Then I happened to look down and I noticed the remains of the spider.

    Dead spider
    Spider after being parasitized by wasp grub

    The grub had essentially completely drained the spider of its body fluids before discarding the dried remains. This explained the sudden increase in size of the grub overnight. It had been feeding on the spider all along, but the final meal killed the spider and caused the grub to almost double in size. Another search of the web added some more pieces to the puzzle in the form of a description of a program with David Attenborough from Life in the Undergrowth. The documentary reveals a strange twist in the final scene between the spider and the grub. The grub apparently secretes a hormone into the spider which alters the spiders behavior causing it to forego the usual neat orb web that it spins every day and instead causes it to spin a loose web that the grub then uses as the stage for spinning its own cocoon.

    Parasitic grub spinning cocoon
    Parasitic wasp grub spinning cocoon

    About five hours after I first saw the grub wriggling in the loose web (it was 10 p.m. at that point), much of its cocoon was complete.

    Completed cocoon
    Nearly completed cocoon

    The next morning, I could see the grub still moving inside a neat sac cocoon made of gold-colored silk. Now I just had to wait and hope I saw the wasp when it emerged.

    Second spider with wasp grub
    Second spider with wasp grub

    That same day I happened to notice another spider on the other screen door on the porch with a similar parasitic grub. Each day since I have checked the cocoons as I walk by.

    completed wasp cocoon
    Completed wasp cocoon

    Two days later, the cocoon looked complete and a little more opaque.

    Developing wasp inside cocoon
    Developing wasp inside cocoon

    Eight days after I first saw the grub wriggling in the web I took a closer look and backlit the cocoon by moving one of twin lights behind it. I could see what appeared to be a developing wasp inside with the dark spot at the top being the head or eyes.

    Empty Wasp Cocoon
    Empty Wasp Cocoon showing exit hole chewed by wasp

    Today (on day 9 since the spider died) I stopped to look and saw the cocoon was empty. You can see the exit hole at the top where the adult wasp chewed its way out. I went to the other cocoon and it was also empty. But then I noticed something else…

    Parasitic Wasp captured by spider
    Parasitic wasp captured by another spider after emerging from cocoon

    A few inches above the cocoon was something wrapped in silk. It was a wasp caught by a different orb spider who happened to have a web just above the loose tangle made by the orb weaver that the wasp in its youthful grub stage had killed. Now the wasp had fallen prey to another spider just as it emerged from the cocoon. The complexities and interrelationships of nature just beyond (literally) our doorstep never ceases to amaze me. Take time to see what you can find outside – you may be astounded.

  • Bottle Opener Bug

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    “In All Things of Nature There is Something of the Marvelous” – Aristotle

    I have always loved that quote as it states in simple terms why I find everything around me so fascinating. I marvel at spectacles such as the Snow Geese at Pocosin Lakes National Wildlife Refuge or the Bison in Yellowstone, but I can also spend hours walking around the garden looking at tiny things. Last week, this critter rode in from the garden on some basil leaves so I took a few moments to obsreve and photograph it.

    Treehopper 1
    Treehopper

    A quick search on bugguide.net revealed it to be a common species of Treehopper, Entylia carinata. It has no official common name, although one writer dubbed it the Keeled Treehopper for its appearance and for the fact that its species name is Latin for keeled. I think it should be called the Bottle Opener Treehopper as it sure looks like something useful you should have on your key chain if it were a bit bigger (it is tiny, only about 5 mm long). They can be variable in color but the keeled notch is distinctive for this species.

    Treehopper
    Treehopper, Entylia carinata

    Like most of its kind, they feed on plant juices and secrete honeydew (a nutritious waste product) that is sought after by ants and other insects. This species is often seen accompanied by ants and one researcher observed that the maturing of eggs and nymphs was much more successful when both the mother and attending ants were present; both acted to drive off potential predators. I found some really cool images online of a female with her eggs and nymphs (http://www.marylandbiodiversity.com/viewSpecies.php?species=6252). I will be out looking for those in the coming weeks.

    So, wherever you are today, take a moment, go outside, and be amazed at the marvelous in nature.

  • Tiny Hummers and Bumblebirds

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    Hummingbird Clearwing, Hemaris thysbe 1
    Hummingbird Clearwing Moth

    During my career at the NC Museum of Natural Sciences I once was forwarded a call from someone that was curious about something they had seen in their yard. She wanted to know what species of tiny hummingbirds were visiting her flowers. After a brief discussion, we came to the conclusion she was seeing one of a group of day-flying moths collectively known as Clearwing Moths, and based on her description of the colors, most likely the aptly named Hummingbird Clearwing.

    Hummingbird Clearwing, Hemaris thysbe 2
    Hummingbird Clearwing at Butterfly Bush

    This common eastern species, Hemaris thysbe, has coloration and foraging behavior reminiscent of a Ruby-throated Hummingbird, but is much smaller. A Hummingbird Clearwing Moth has a wingspan of about 1.5 – 2 inches, whereas the bird, the Ruby-throated Hummingbird, has a wingspan of 4.5 inches. Yet it is easy to see how people could mistake these diminutive rapid fliers for the bird. They hover and flit from flower to flower sipping nectar with their long proboscis. Their wings have reddish borders and they often have a greenish hue to the “hairs” on their stout bodies. These photographs of the adult moths were taken last week while visiting my parent’s in southwest Virginia. They have several Butterfly Bushes (Buddleia sp.) which are magnets for these beautiful moths.

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    Hummingbird Clearwing wingbeat

    One thing you notice when you watch one of these moths is the blur of their wings as they hover and feed. Try as I might, I could only occasionally get part of both wings in focus even at high shutter speeds. No wonder, as it is estimated they beat their wings 30-35 times per second (compare that to a Ruby-throated Hummingbird with an average of 50-60 beats per second). One thing the rapid burst of photos did reveal is the pattern of movement in the wings – the figure-8 motion (the photo above shows the start of the backward sweep of the figure 8), which provides lift in both directions.

    Snowberry Clearwing, Hemaris diffinis 2
    Snowberry Clearwing

    I also noticed several individuals of the similar-looking Snowberry Clearwing (Hemaris diffinis) feeding on the Butterfly Bushes. They closely mimic bumblebees in coloration and are often called Bumblebee Moths. In one online discussion forum I even saw someone refer to these as looking half hummingbird, half bumblebee – a bumblebird! The main differences between them and the Hummingbird Clearwing is that this species tends to be slightly smaller and has a blackish abdomen with a yellow band (sometimes not complete) near the tip.

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    Snowberry Clearwing on Butterfly Bush

    Both species have a long proboscis they insert into flowers to obtain nectar. They often place their front pair of legs on the flower as they hover and feed.

    Hummingbird Clearwing caterpilar
    Hummingbird Clearwing caterpillar

    Both Hummingbird and Snowberry Clearwings are members of the hawk moth or sphinx moth family, Sphingidae. They are among the few strictly diurnal (day-flying) members of that family and are found throughout most of the eastern United States and Canada. Their caterpillars are similar to many other sphinx moth larvae in that they have a distinctive curved horn on their posterior end (caterpillars of this family are often called hornworms). The Hummingbird Clearwing’s horn is often bluish and they have a row of orange and white spots along each side surrounding the breathing pores (spiracles).

    Snowberry Clearwing caterpillar
    Snowberry Clearwing caterpillar

    Snowberry Clearwing larvae have blackened dots along their spiracles and a horn that is yellow at the base with a black tip. Both species use various species of Haw (Viburnum sp.) and Honeysuckle (Lonicera sp.) as host plants. I always look for them on Arrowwood Viburnum and Coral Honeysuckle in my area.

    Snowberry Clearwing, Hemaris diffinis 3
    Snowberry Clearwing cruising in toward a meal showing curled proboscis

    If you have either of these host plants in your garden or woods, be on the lookout for the adults as they cruise and hover at your flowers in search of nectar. I see them at a wide variety of plants from non-natives like Butterfly Bush to native beauties such as Bee Balm and Phlox. Every time I see one I can’t help but pause and enjoy…and sometimes I even stalk them for an hour or more trying to get just the right photo, but I always want a better one…

    Hummingbird Clearwing, Hemaris thysbe 5
    Hummingbird Clearwing

  • Dressed for Success

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    And what’s a butterfly? At best, He’s but a caterpillar, drest.      John Grey

    And there is one species of caterpillar that dresses better than any other – the Camouflaged Looper, Synchlora aerata. This is the unusual larva of the Wavy-lined Emerald Moth (okay, the quote isn’t quite right in this case…).

    Camouflage Looper
    Can you see the caterpillar?

    Every time I am out in the garden I always take a few moments to just look around for interesting critters. As I watched a few pollinators on the Blazing Star (Liatris sp.) yesterday, I noticed something move. But there was nothing there…then it moved again, and I knew what it was – a Camouflaged Looper. This caterpillar has the unusual habit of disguising itself by cutting plant parts from the flowers on which it is feeding and sticking them onto its dorsal surface. The larvae feed on a wide variety of plants although I have most often found them on Blazing Star, Black-eyed Susan, and a few other yellow composite flowers.

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    Camouflage Looper and its “costume”

    In a 1979 article in The Journal of the Lepidopterists’ Society, Dr. Miklos Treiber, of the University of North Carolina, wrote about the camouflage abilities of these inchworms. The larvae cut off flower parts, seeds, and even entire flowers, and attach them to needle-like projections on their upper body surface. In a series of experiments he removed their floral covering and they immediately  began to replace the camouflage.

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    Camouflaged Looper on yellow composite

    Furthermore, when moved from one flower type to another (purple to yellow in his case) the larvae began to replace their old camouflage with flower fragments from the new plant.

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    Camouflaged Looper on Blazing Star

    He also noted that the fragments are passed through the mouth of the larva before being attached and that a mucilaginous substance (aka “caterpillar spit”) was secreted by the larva onto the fragments. He speculated that this substance seems to play a role in maintaining the freshness in these fragments. The caterpillars also maintain the effectiveness of the covering by replacing withered floral parts with fresh ones.

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    Camouflaged Looper looks like plant debris when not on matching flower

    Dr. Treibe hypothesized that this looper’s ability to change disguises allows it to have a much more varied diet than some other caterpillars because it isn’t restricted to eating only those flowers or plant parts that it resembles in appearance. And I noticed that even when it is moving between flowers and is on a stem, leaf or other background, the caterpillar simply looks like some plant debris rather than a potentially tasty meal for any passing bird.

  • Bullet Frass

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    Silver-spotted Skipper 1
    Silver-spotted Skipper on Blazing Star

    It may seem like an odd title for a post on one of our more common backyard butterflies, but I promise I’ll explain it in a moment. You may have seen this distinctively marked species as it darts about your yard from flower to flower. It is the Silver-spotted Skipper, one of, if not the, largest of our skippers.  Skippers are small to medium-sized insects in the family Hesperiidae. They are named for their fast, darting flight. Although more closely related to butterflies than moths, skippers more closely resemble many moth species in appearance by having stout, somewhat “hairy” bodies that are rather dull-colored.

    Hoary Edge Skipper
    Hoary Edge Skipper with tear in hind wing

    For me, skippers have always been the sparrows of the lepidopteran world – those dull-colored, similar-looking small fliers that are difficult to tell apart. One reference put it succinctly – many species of skippers look frustratingly alike. Luckily, this species is a good one to practice your skipper observation skills on as there is really only one other skipper in our area that can be confused with the Silver-spotted Skipper. The Hoary Edge Skipper is slightly smaller and much less common than the Silver-spotted Skipper. A close look shows the diffuse white patch on the Hoary Edge Skipper is further back on the hind wing whereas the Silver-Spotted Skipper has the white more in the center of the hind wing.

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    Silver-spotted Skipper

    The Silver-spotted Skippers are nectaring primarily on the Blazing Star and Bee Balm in the garden. They apparently almost never visit yellow flowers of which I have many species blooming right now.

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    Silver-spotted Skipper larval head capsule showing false eye spots

    But, as is often the case for me, it is the caterpillar which I find most interesting. Like most skipper larvae, they are rarely seen because they spend much of the day in folded leaf shelters and come out to feed primarily at night. The caterpillar chews and pulls together leaf fragments with silk to form a shelter. This provides some protection from many predators. When you do find one, the first thing you notice about later instar larvae are the bold orange false eye spots.

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    Silver-spotted Skipper larva in exposed leaf shelter

    But the really amazing thing is the other strategy they employ for avoiding predators (and hence the unusual title of this post). Studies have shown that many potential predators of caterpillars (such as wasps, who feed them to their own larvae) are attracted to the chemical cues in frass (the fancy word for insect poop). So, if you build a little shelter to hide in, you had better fling your frass out the door if you don’t want want hungry wasps to come knocking. Turns out these skipper larvae have a structure with the unpleasant-sounding name of anal comb. They use it to launch their frass pellets an impressive distance away from the shelter. One researcher showed that a 4-cm long Silver-spotted Skipper larva could launch a pellet an incredible 153 cm, or 38 times its body length. I’ve heard of tossing buffalo chips out west, but frass flinging? You just never know what potential new sport you might find right outside in your garden.

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