Friday, October 23, 2020

Updates to Northwest Butterflies

Normally this time of year I'd be heading to the NW Leps Workshop in Corvallis for a weekend gathering of regional lepidopterists, probably my favorite butterfly-related event all year and one of the only times people can buy my books without the extra cost of shipping. However, due to the combination of a building remodeling project and COVID restrictions, the meeting has been changed to a virtual chat. Meanwhile, after nearly three years in business I've been making some updates to my storefront (list below).

So to celebrate three years in business and honor my NW Leps customers, I am offering 20% off all orders placed on October 24 through November 21. Go to and use the code NWLEPS2020 during checkout to claim the discount!

Some of the changes:

Digital downloads -- I have plans to expand this but for now there are two items available for free:

    • Comprehensive checklist of the butterflies of Washington. This is a PDF that myself and the rest of the authors freely distribute. It is offered here so anyone can check for new updates and download immediately without waiting for emails.
    • List of errata for Butterflies of the Pacific Northwest along with taxonomic (Genus/species name) updates.

Butterflies of the Pacific Northwest by myself and Robert Michael Pyle - I have 20 copies available that I will sign. If they sell out I can order more.

I've added a page with shipping cost information in an effort to provide up-front costs so you aren't surprised when you get to the checkout. Instead of auto-calculating shipping during checkout, I now have set shipping costs based on my averages over the past three years. I also balanced it with slightly reduced book prices. This means people in the Pacific Northwest will save between $0.50-2.00 compared to former order totals, and people in eastern states may save as much as $7 compared to former totals.

New photo products -- I have a limited number of vinyl stickers made from my photographs. Depending on how these sell, I may develop some additional options. I also added a new magnet option: a kiss cut Ceanothus Silk Moth adult. Let me know if you have any requests or suggestions!

Ceanothus Silk Moth
mock-up of kiss cut design for stickers and magnets

Friday, March 27, 2020

Species Profile: Hera Buckmoth - Hemileuca hera

Hera Buckmoth or Hera Sheepmoth (Hemileuca hera) is a large, black and white, day-flying moth found in sagebrush-steppe habitat across the western United States. In our area, it occurs in eastern Oregon and Washington. See my earlier post on Hemileuca species in the Pacific Northwest for other details about its life history. Hera is notoriously difficult to rear and there are few published descriptions. While out looking for butterflies (unsuccessfully, due to the cool, overcast weather), a little black clump on some sagebrush caught the corner of my eye. Closer inspection revealed them to be first instar Hera larvae! Super excited, I clipped off the branch and carried them home to rear, ignoring the fact they feed exclusively on sagebrush in desert habitat and I live on the west side of the Cascades, far from sagebrush. Thus my adventure began!

Sagebrush-steppe habitat in eastern Kittitas County, WA where I found Hemileuca hera larvae on April 20, 2019.
Hera Buckmoth (Hemileuca hera) - late 1st instar larvae on basin sagebrush (Artemisia tridentata) in Kittitas County.

A day after I found the larvae, they began molting into the second instar. The light brown larvae on the right (below) just molted. The lighter gray larvae on the top left and bottom left molted earlier, while the dark black larvae are about to molt.

Hera Buckmoth (Hemileuca hera) - larvae molting into 2nd instar on April 21, 2019.

Hera Buckmoth (Hemileuca hera) - 2nd instar larva.

During the first week, I fed the larvae on cut basin sagebrush (Artemisia tridentata) in a small cage (below). I kept the ends wrapped in wet paper towels placed in plastic baggies and secured around the top with twist ties and binder clips. The cuttings stayed surprisingly fresh for at least five days before starting to yellow.

Hera Buckmoth (Hemileuca hera) - my rearing setup for the first week.

Hera Buckmoth (Hemileuca hera) - 2nd instar larvae.
Second and third instar larvae were solid black with black bristles and silvery hairs. They moved and fed together in such tight bundles that it was impossible for me to accurately count how many there were. Because of this, I am uncertain how many might have died, although I was very careful to clean the cage and examine the leaves and branches when replacing food and I never noticed any dead larvae. My attempts at counting the larvae in the 3rd and 4th instars always resulted in 20-21. One died in 5th instar and I ended with 18 pupae, so the true total was probably 20 and I must have lost a larva in the 3rd or 4th instar.

Hera Buckmoth (Hemileuca hera) - 3rd instar larva.

After the first week with cuttings, I fed the larvae on potted Artemisia tridentata for two weeks. Unfortunately, the sagebrush didn't do well and started to yellow so I was back to obtaining fresh cuttings the following two weeks. I loaded up my hungry caterpillars for a 600 mile round trip drive (I'm a very dedicated caterpillar momma!). I found some lush sagebrush growing on the side of a road pullout before the mouth of the Deschutes River in the Columbia Gorge. It had big, long leaves compared to most of the surrounding sage, which I didn't think much of at the moment, figured it just had more moisture or something. I loaded up a bag full of cuttings and headed home. A colleague commented that the leaves looked different in my pictures and after studying information on different sagebrush species, I tentatively identified it as Artemisia cana, silver sagebrush. Hera seem to exclusively use A. tridentata throughout their range, only one larva has ever been found on A. cana in the wild, so I was a bit nervous that I might be damaging my chances of successfully rearing these picky cats, but they voraciously took to the fresh cuttings and continued feeding well on it for the next two weeks until I was able to purchase several pots of A. tridentata I then switched them back to.

Hera Buckmoth (Hemileuca hera) - 3rd and 4th instar larvae on Artemisia cana.

Fourth instar larvae exhibited orange-yellow bristles on the two dorsal (back) rows and white spiracles. In all of my rearings of Hemileuca eglanterina, larvae of that species look similar to hera at this stage, except that eglanterina has these orange bristles on all spines dorsally and laterally through most instars.

Aren't they cute? But don't touch! As with all other Hemileuca species, the caterpillars have urticating (stinging) hairs that feel like running your hand through a stinging nettle patch. You might get away with allowing the larvae to crawl on your hand without being stung, just don't try to pick them up or touch their backs!

Hera Buckmoth (Hemileuca hera) - 4th instar larva on Artemisia cana.
Hera Buckmoth (Hemileuca hera) - 4th instar larva on Artemisia cana.

Hera really are quite beautiful in the fifth (final) instar! They have variable markings in pale yellow and pinkish cream on their bodies, white spiracles (breathing holes), non-stinging silvery hairs on their body, long black spines with either black or yellow branches tipped with silver stinging hairs.

Hera Buckmoth (Hemileuca hera) - closeup of 5th instar larva.
Up to this point, the larvae developed steadily, molting into the next instar every 12-13 days.

Hera Buckmoth (Hemileuca hera) - 5th instar larvae on Artemisia tridentata.
At this point, the larvae had been in the 5th instar for two weeks. I was expecting them to prepare for pupation any day, and they did spend half their time crawling around the cage, but they acted more like they were looking for food, in spite of there being plenty, and as soon as I picked them up (with a paintbrush!) and put back on the plants, they always went back to eating. This became a daily routine, every morning and evening, to carefully transfer the larvae from the bottom of the cage back onto the plants. This is likely the time when larvae in the wild are spreading out to feed singly instead of in large groups. I had enough potted plants to keep 1-2 larvae per plant, but the plants were only 10-12 inch tall plants from a native plant nursery. Plenty of leaves for them to eat, but possibly not enough space for this apparently super picky stage of their development.

Hera Buckmoth (Hemileuca hera) - 5th instar larvae on Artemisia tridentata plugs placed in a PVC pipe and masking
 tape grid to try to keep them spaced apart. However, this made it difficult for the larvae to find
 the plants again after dropping off.

Hera Buckmoth (Hemileuca hera) - 5th instar larva on Artemisia tridentata.

Unless the larvae are out feeding near the ends of the branches, it would be easy to overlook these larvae if you didn't have a really good search image as they blend into the silvery glint and broken shadows of the sagebrush.

Hera Buckmoth (Hemileuca hera) - 5th instar larva on Artemisia tridentata; it is surprisingly well-camouflaged!

Hera Buckmoth (Hemileuca hera) - 5th instar larva on Artemisia tridentata.
At this point (weeks 8-10), the potted sagebrush was half eaten so I placed all the plugs into a box (figured this would also provide a nice dark place for pupating) and also provided more A. tridentata cuttings. Although the larvae continued to drop off the plants and crawl all over the cage, this setup made it easier for them to find the leaves again without me putting them back on the plants.

Hera Buckmoth (Hemileuca hera) - rearing cage with potted and cut sagebrush,
set outside for sun exposure, temperatures between 85-92F and good ventilation.

You may have noticed at this point that I kept the larvae inside or outside at different points. I experimented with different conditions because Hera are used to being fully exposed to sun and wind. Living on the west side, outdoor conditions in April-May are cloudy and in the mid-60s at best, with higher humidity than sagebrush-steppe habitat. Keeping the larvae outside gave them 1-2 hours of sun per day and a bit of fresh air, but was higher humidity (60-80% RH) and cooler than I thought they appreciated. Keeping them inside gave them a steady 70-73 degrees 24 hours a day and lower humidity (35-40% RH) but only provided what little sunlight could reach through my windows. After a couple weeks, I had an idea to set up my full-spectrum plant light and purchased a UVA-UVB bulb rated for desert reptiles. I figured that if reptiles need that spectrum to keep them healthy, my caterpillars would probably benefit as well. Here is what my setup looked like, with adjustable height of the lamps depending on what cages I was using.

Hera Buckmoth (Hemileuca hera) - rearing cage setup indoors with full-spectrum plant light
and a UVA/UVB bulb rated for desert reptiles in an attempt to replicate sun exposure.

FINALLY!!! After over a month (37+ days to be exact!) of dilly-dallying, the larvae finally started showing definite signs of preparing to pupate...

Hera Buckmoth (Hemileuca hera) - prepupal larva.

Over the years, I've played around with different items for ground-pupating moths. In this case, I was concerned that keeping the larvae in a closed container like a bucket or gallon jar might not be ventilated enough for this desert species. Also, I was about to head out on a two week road trip and didn't want to leave them in a mesh cage that could easily be disturbed with jostling around and moving luggage. I pulled out my blancher - perfect! Lots of holes for ventilation but just small enough the larvae couldn't fit through them, it's dark so mimics being underground, and it is small enough that I could fill it with several ripped-up and crumpled paper towels without using up a whole roll. I could hear them rustling around in it for a few days and then it was all quiet.

Hera Buckmoth (Hemileuca hera) - prepupal larvae.

Around 8-10 days later, I opened the blancher and carefully searched through the paper towels to find all the pupae...18 total!

Hera Buckmoth (Hemileuca hera) - prepupal larvae and pupae.

Back home from my trip, I tucked all the pupae between folds of a cotton towel placed in a cage kept on my porch to be overwintered. One of them had other ideas though: this gorgeous female emerged on September 22, 2019, much to my surprise! If nothing else emerges this coming summer, I will still feel like I was successful to at least get one of these fussy beauties all the way through to adulthood.

Hera Buckmoth (Hemileuca hera) - adult female.

Tuesday, March 24, 2020

Videos for a rainy (or isolated) day...

Hi folks! Whether you are working from home but dreaming of sunny days afield (or just plain dreaming of normal days), or are stuck at home trying to figure out how to keep yourself occupied, here are some video recordings you might find interesting. Al Wagar, a member of the Washington Butterfly Association (WBA), has kindly shared a list of his videos grouped by format. You may also visit his YouTube home page to browse through these and other nature videos as well. I have not watched all of these videos but I checked each link to make sure it works and hyperlinked them to the subject line instead of pasting the full path name. Let me know if you run into any issues (use my email contact on the left) and I hope you find these useful!

WBA Programs (Monthly Seattle Meetings) and Identification Videos



Yake – Mongolia








Species Profiles & Short Presentations – all by Dave Nunnallee

WBA Field Trips & Conference Videos





Sunday, March 22, 2020

Species Profile: Nevada Buckmoth - Hemileuca nevadensis

Nevada Buckmoth (Hemileuca nevadensis) is a striking day-flying moth found in riparian habitats ranging across much of the arid lands of the western United States and into the upper Midwest. See my earlier post on Hemileuca species in the Pacific Northwest for other details about its life history. Although I have yet to see it in the wild, I obtained eggs from a breeder and reared them in 2010. I kept them in a cage indoors and fed them on willow cuttings. I cut larger branches that produced roots after a week or two of being kept in jugs of water, which helped maintain fresh food material for the larvae. I switched between cuttings of Salix lasiandra (Pacific willow) and S. fragilis (crack willow or brittle willow) and the larvae readily took to both throughout their growth.

The solid black first instar larvae look identical to other Hemileuca species. Second instar (L2) is similar to H. eglanterina, black with bright orange bristles. They begin to show a little yellow on their sides by the end of L2. The yellow increases in L3 and by L4 they are almost solid yellow with black markings, light orange/yellow and black bristles, and dark red-brown heads and legs. Adults are boldly marked in black and white with bits of reddish-orange hairs around their legs and thorax, and males have a reddish-orange-tipped abdomen.

Nevada Buckmoth (Hemileuca nevadensis) - hatching eggs
 Nevada Buckmoths lay their eggs in a ring around twigs. Larvae feed in together in clusters until the fourth instar when they start to spread out.

Nevada Buckmoth (Hemileuca nevadensis) - newly hatched larvae checking out some fresh willow.
Nevada Buckmoth (Hemileuca nevadensis) - 1st instar larvae after a few days of feeding.
Caterpillars of Hemileuca species have urticating (stinging) hairs.
Paintbrushes are essential for moving them to fresh food unless you want to be stung!
Nevada Buckmoth (Hemileuca nevadensis) - 2nd instar, on the march looking for more food.
Nevada Buckmoth (Hemileuca nevadensis) - newly molted into 3rd instar.
Nevada Buckmoth (Hemileuca nevadensis) - late 3rd instar larvae.
Nevada Buckmoth (Hemileuca nevadensis) - newly molted 4th instar larvae.
Nevada Buckmoth (Hemileuca nevadensis) - 4th instar larvae.
Nevada Buckmoth (Hemileuca nevadensis) - early 5th instar larva.
Nevada Buckmoth (Hemileuca nevadensis) - 5th instar larvae.
Nevada Buckmoth (Hemileuca nevadensis) - 5th instar larva.
Nevada Buckmoth (Hemileuca nevadensis) - prepupal larvae.
Nevada Buckmoth (Hemileuca nevadensis) - pupa emerging from the larval skin.
Nevada Buckmoth (Hemileuca nevadensis) - pupa emerging from the larval skin.
Nevada Buckmoth (Hemileuca nevadensis) - pupa emerging from the larval skin.
Nevada Buckmoth (Hemileuca nevadensis) - new pupa.
Nevada Buckmoth (Hemileuca nevadensis) - pupa nearing time for adult to emerge: note the wing pattern showing.
Nevada Buckmoth (Hemileuca nevadensis) - newly eclosed female.
Nevada Buckmoth (Hemileuca nevadensis) - newly eclosed female.
Nevada Buckmoth (Hemileuca nevadensis) - female.
Nevada Buckmoth (Hemileuca nevadensis) - male.
Nevada Buckmoth (Hemileuca nevadensis) - male.
Nevada Buckmoth (Hemileuca nevadensis) - male "playing dead".
Buckmoth/sheepmoth (Hemileuca spp.) adults have an interesting defense mechanism: when they feel threatened, such as if they are suddenly grabbed or jostled, they fold their wings back, curl their body and drop to the ground, laying motionless for up to several minutes before becoming active again and crawling or flying up to a new branch.

Saturday, March 21, 2020

Species profile: Hemileuca of the northwest

There are four species of Hemileuca (buckmoths or sheepmoths) in the Pacific Northwest: Nevada Buckmoth (H. nevadensis), Elegant Sheepmoth (H. eglanterina), Nuttall's Sheepmoth (H. nuttalli) and Hera Buckmoth (H. hera).

I posted a short profile here on Hemileuca eglanterina in 2011. Over the next few days, I plan to post profiles of H. hera  and H. nevadensis. Hemileuca nuttalli is the only one of these four species I have yet to rear or even see, hopefully I will be able to post photos of it in the coming years!

Range & Flight Period
The Nevada Buckmoth is least common, occurring in willow habitats along the Snake River at the Oregon-Idaho border, the Columbia River at the eastern Washington-Oregon border, and as far north as George, Washington. It likely occurs elsewhere in eastern Oregon and southern Idaho, but often goes unnoticed due to the adults flying in late September and October. Nuttall's Sheepmoth occurs in sage-steppe habitat throughout eastern Washington, eastern Oregon and southern Idaho. It flies from late July to September. Hera Buckmoth occurs throughout the same area as Nuttall's and fly during the same period, but Hera appear to be more common. Elegant Sheepmoths are the most common and widespread of these four species in our area and the only one to occur west of the Cascades. They can be found in most woodland, prairie and upland habitats in Washington, Oregon and Idaho and fly from late May to September, peaking in July. All four species are day-flying and are often mistaken for butterflies by the casual observer.

Overwintering stage:
Nevada Buckmoth overwinters as eggs and therefore has a one-year life cycle.
Elegant Sheepmoth overwinters as eggs (one-year life cycle) in most areas. Higher elevation and northern populations overwinter as both eggs and pupae and have a two-year life cycle.
Hera Buckmoth and Nuttall's Sheepmoth usually overwinter as both eggs and pupae for a two-year life cycle, but some may have a one-year cycle in warmer seasons or low elevations.

Larval host:
Nevada Buckmoth feeds on willows and cottonwoods.
Hera Buckmoth feeds on sagebrush (Artemisia spp.).
Nuttall's Sheepmoth feeds on bitterbrush (Purshia tridentata) and snowberry (Symphoricarpos spp.).
Elegant Sheepmoth feeds on a variety of hardwood trees and shrubs including wild rose (Rosa spp.), hawthorn (Crataegus spp.), serviceberry (Amelanchier alnifolia), snowberry (Symphoricarpos spp.), cherries (Prunus spp.), snowbrush/buckbrush (Ceanothus spp.), willows (Salix spp.), and bitterbrush (Purshia tridentata).

Adults of Hemileuca, like other members of the Saturniidae family, do not have developed mouthparts and therefore do not feed.

Nevada Buckmoth 50-70 mm
Elegant Sheepmoth 65-87 mm
Hera Buckmoth 71-93 mm
Nuttall's Sheepmoth 69-83 mm

Nevada Buckmoth - Hemileuca nevadensis (male)

Elegant Sheepmoth - Hemileuca eglanterina (male)
Hera Sheepmoth - Hemileuca hera (female)