Monarch population comeback

Back in winter 2012 I posted about a monarch butterfly deformed upon emerging from its pupa.  I went on about how maybe the winter timing of its emergence had something to do with its deformity or difficulty eclosing.

This was clearly incorrect as the butterflies, and all of the caterpillars mentioned in that post as well, was infected with the OE parasite (Ophryocystis elektroscirrha).  The caterpillars ingest the spores of the parasite as they feed, which have been deposited there by their infected mother as she laid the eggs.

In an earlier post I was observing massive population of caterpillars decimating the milkweed, which had also been less than vigorous for some time at that point.  There was also a weak emerged adult in that post, likely a less severely infested victim of OE.

Turns out that winter 2012 was the peak of our OE infestation.  The emerging adults were so heavily infested they were unable to mate and reproduce, resulting in population crash.  I also removed all of the milkweed in January 2013 in the interest of preventing the spread of the parasite. 2013 there were zero monarchs about the estate.  At the house across the street, a lush stand of milkweed started up mid year and this adult emerged apparently healthy.

Through 2014 the milkweed stand across the street has prospered along with the monarchs and milkweed bugs.

In spring I found a pupating monarch on a new seedling milkweed in my own parkway strip, which later successfully emerged.  So perhaps the OE has ebbed.  Does population density play a part in the intensity of the infestation?  I think removal of milkweed supporting infected populations may be a good idea but also being aware of the signs of infestation although in light infestions there may be no indication short of microscopic examination.

Photo Dump: Papilio zelicaon Edition

Anise swallowtail story, that took place in August 2011, ends in oddness.

A fat mature caterpillar in mid-August contemplates the choice between continuing to eat the fennel and pupation.  Eating wins out for a few more days . . . ha! notice the green stink bug on the right of this photo, recently molted!  Anyway,

eventually pupation is inevitable and the caterpillar assumes the position, spins a silk pad at the rear end and a silk safety line around the middle and waits.

Next day: the fresh pupa full of butterfly-flavored hope.

Three days later, the pupa has been split at the top (head area).
There was some brownish stuff inside.  Predation?  Parasitoid?  Mechanical accident?

The damaged pupa hung there and dried; its silk line broken.

one day I caught this bug, Creontiades rubrinervis, lurking around.  It even went inside the empty shell, seeking what?

Two previously undisclosed wasps

With the buckwheat and the fennel both in full bloom, nectar feeders of many stripes and colors are being attracted to the back 40.  On a recent day I noticed a large black wasp up in the fennel among the flowers.  Using Natural History of OC as my reference, I'm thinking this is a member of genus Palmodes, a thread-waisted wasp.  If so, the female stocks her nest with katydids.  Possibly woe to those cute microcentrum californicum I saw earlier in summer.

Anyway, this large wasp spent a lot of time among the flowers, occasionally being harassed by a polistes or mud dauber.

Another unfamiliar wasp caught my eye among the buckwheat flowers.  NHOC has a photo posted that looks exactly like this, labelled Campsomeris pilipes.  

The larvae of this species is said to parasitize ground dwelling beetle larvae such as Japanese beetles; maybe green peach beetles?

Carnival of Carnivores

I was watering the shrubbery this morning as the sun began climbing to what was predicted to be an apex of unexpectedly ridiculous blistering heat, when a big black spider climbing around in the milkweed caught my eye.  It was a Bold Jumping Spider (I love that name--if you've got it, flaunt it), Phidippus audax with another spider caught firmly in its chelicerae, aka fangs.

The unfortunate prey looks to be either a funnel web spider or maybe a young araneus orb weaver.  Hard to tell with its body all bunched up.  We know it is brown, it appears to be moderately hairy.

And it is a spider that wraps its prey in silk.  Here is a honeybee that was, I presume, the prey of the spider that became prey.  It is hanging among the remains of a web among the milkweed leaves not very far at all from the spider drama.

Milichid fly on honeybee spider prey

Interestingly, the honeybee prey has attracted several milichid flies, sometimes referred to as freeloader flies.  These small predators take advantage of the time while a spider waits for its wrapped prey to predigest, and feed on this easily available nutrient source usually as the spider looks on.  In this case, the flies have the bee all to themselves.  This mode of feeding is known as kleptoparasitism, stealing food or prey from another organism that has captured or even prepared it for itself.  The parasite is the milichids, the parasitized is the spider.

As I watched the bold jumper sauntered down the milkweed stalk, then paused to focus my camera with its acute eyesight centered in the Anterior median eyes (the two big ones in the middle of the spider's face).  Then, spider and spider prey disappeared into the shade of the shrubbery.

Evidence of Katydids

I found these katydid eggs affixed in two rows along a small twig by my mailbox. Which species of katydid laid them?

Scudderia furcata (forktailed bush katydid) is common in my garden, but she inserts her eggs between the tissue layers on the edge of leaves so I knew these eggs couldn't be her doing.

Phaneroptera nana, the Mediterranean katydid, recent import to OC would seem a likely suspect, except I found 2 citations stating the eggs are inserted into plant tissue (1 said apple leaves, the other outer bark of grapevines.

Microcentrum sp eggs are said to look like rows of small overlapped canteloupe seeds. The only microcentrum said to occur in CA (per bugguide) is californicum, however no katydid I've seen here has the brown patch on the thorax. M. rhombifolium seen here on Arthropods of Orange County (therefore, presumably occuring here in OC, contrary to info on bugguide saying it's not found in California) could have been the one pictured here (and therefore misidentified). Hmmm.

So which is it: 3 species of katydid in my small domain or just the two?

By the way these eggs were parasitized by a wasp, of unknown and possibly unknowable species.

Meanwhile, a katydid nymph is found on a nearby ruellia stem, offering its cuteness as a diversion from worries about identification and other serious matters.

Hello Stranger

So I was standing in the driveway next to the cactus collection about an hour before sunset on a day last month when I heard an unusual buzz go by. I'm not saying I can id any bug by its buzz, but when you've been observing insects awhile you get tuned into the particular sounds each species makes as it flies. So I recognized that this one was different: a loud-ish, dry/clattery sound of a lower than average pitch. The maker of the sound became apparent as it landed on a pod of the nearby feathery cassia (Senna artemisioides): a large (body length about 3/4", wingspan a bit more) fly with highly decorated wings and unusual (kinda scary-looking) eyes.

This is a bee fly (family bombyliidae) in genus Xenox. I'm semi-educated-guessing the species as X. habrosus based on comparison of the wing markings and appearance of the thorax in photos here. (Thanks guys at NatHist of OC). The generic name xenox comes from the Greek for stranger or alien, and those weird bug-eyes must have inspired the name. This fly has been a stranger to my property, this being the first time I've seen (or heard) it. This particular individual hung out on the cassia pod until after dark . . . maybe spent the night there, but was gone by the next day.

These bee flies parasitize solitary bees, such as the valley carpenter bees (xylocopa varipuncta) which are so plentiful around here. The female fly places her egg inside the entrance to the bee's nest where the fly larva feeds on the provender placed there for the bee larvae for part of its life cycle. Then the fly larva switches to feeding on the bee larva itself.

There has not been another sighting of this alien since July 24, but I've got my ears on for them.

Two Typical Bugs

Here are two typical bugs, and by that I mean certain buggies of the order hemiptera grouped together in the suborder heteroptera and also called true bugs (as opposed to lying stinking backstabbing bugs) or typical bugs. As such these bugs possess certain typical features: mouthparts elongated into a beak for piercing tissue (usually plant but sometimes animal), partially hardened forewings that do not cover the membranous portion or the hind wings, an "X" across the back of the bug formed by the triangular scuttelum and the leading edge of the folded wings. Their metamorphosis is incomplete, meaning they grow through several stages that resemble the adult and do not pupate. They typically use the same food source throughout their life stages, and often are agricultural or garden pests.

The first photo is an adult harlequin bug, Murgantia histrionica. It is resting on a sprig of sweet alyssum (lobularia maritima) that shows typical stippling damage from the feeding of these bugs. Their preferred food is most any plant in the cabbage family, but they will feed on other stuff in the absence of crucifers. What usually happens in my garden is the alyssum sprouts from seed, and grows nicely for a month or two until the harlequin population builds up and the plants look like that shown here. I get sick of looking at them and pull them out; the bugs just seem to go away. The weather turns cool, the alyssum seeds sprout, and we start all over again.

The second photo is of a bug quite common on flowers in my garden, and formerly identified here only as a "mirid bug". Thanks to Peter Bryant and the experts at Bugguide I can now make your acquaintance to Creontiades rubrinervis, which is quite a mouthful and there is unfortunately no common name yet available as far as I know. Here is a nice photo of the nymph stage, very attractive little buggies often seen in my garden and on this blog. This post has some interesting photos of an adult C. rubrinervis that had been parasitised. These mirid bugs are plant feeders and I guess if their numbers built up they could be damaging; apparently the parasites and predators are keeping them in check in my garden.

Recently, at the Public Library

I was walking by the Tustin Public Library recently when I happened to notice some butterfly pupae hanging within the vine that clambors over the chain link fence there between the old decrepit library and the new one that is under construction. OK, in reality I was purposefully looking for signs of gulf fritillaries since the vine is passion vine and that is the exclusive larval food for agraulis vanillae. The chrysalises closely resemble dead leaves among the foliage, I suppose as camoflage protection from predators. On close inspection, though, you can see small round holes in the outer shell, evidence of apparent parasitization of the developing butterfly inside. This chysalis had two holes, maybe exit holes of the developed adult parasite or entrance holes for the larval parasite or the egg-laying female.


Some caterpillars:













At the time the parasitized chrysalises were found, some well developed caterpillars were also on the vine doing their worst. When I returned a couple of weeks later I found these larvae had pupated, as there were some new chysalises hanging among the passion vine tendrils. This one had a suspiciously tenacious fly or wasp on it which clung to the chrysalis even when I disturbed the nearby foliage for a clearer view, apparently unwilling to give up its prey? host? or just a convenient resting place? The thing resembles a milichiid fly, which are famous for glomming onto prey captured by other predators, usually spiders. Guilty as charged, just a simple thief, or an innocent caught in the wrong place at the wrong time?

The gulf fritillary has become common around here ever since gardeners started growing passion vine, enabling the species to breed. I see them flying most of the year; they nectar frequently at pentas, basil, and lantana in my garden. Someone said about 1 in 600 butterfly eggs make it to a successful breeding adult. With those odds I like to appreciate most every one I see.

The chain link fence where the passion vine grows that nurtures this butterfly population may be torn down soon, when the new library is completed. I'm thinking the passion vine will go, too, to be replaced by agapanthas, daylilies, privet hedges, etc. So any agraulis vanillae which arise from this vine shortly before its demise will need to seek out a new passiflora on which to lay eggs. Maybe I'll plant one; it's not like the gulf fritillary is endangered, but on the other hand neither is empty space along my property line.

4/27 Update: So I was walking by the library today. The sign is up on the front of the building. Yep, those are flowering pear trees lining the walk to the front doors. Oh and there will also be bird of paradise planted someday soon, so we can add one more the plant diversity here. The fence and the passion vine had been removed. A gulf fritillary approached from the north, glided over the roof of the old library, and couldn't help but notice that her breeding ground was gone. She flew off.

Also, I have noticed many of these butterflies flying in my yard the past couple days. Several of them popped out from the ligustrum japonicum texanum hedge along the driveway . . . a bit of a mystery as 1) the privet is not in bloom and therefore not available as a nectar source, and 2) privet is not remotely related to passionvine and couldn't be used as (or even mistaken for?) a larval food plant.

Evidence of Mantis Egg Parasites

I was checking on the ootheca the other day . . . mantis egg cases, that would be. I know where three of them are/on the crow/under the picnic bench/on the gourd earth, and so I take a look now and then, mostly just to look because the mantis nymphs aren't expected to hatch for several months, in mid-summer. So I was surprised to see these tiny round holes in one of them (the one on the earth); they looked to me just like egg-parasite exit holes on glassy-winged sharpshooter egg masses.

I searched around the internets but couldn't find any information specific to southern CA; but as we know mantis egg parasites do exist here. I did find out about some Australian parasitic wasps which actually hitch a ride under the wing of a newly matured female mantis. The female wasp waits (up to several months) until the mantis has mated and is laying its eggs within the oothecum, then creeps down to the foamy mass and locates a mantis egg with its long ovipositor, dropping an egg there. It repeats the process and then the foamy covering hardens, protecting the parasites as they consume the mantis eggs.

During my search I also ran across The Art of Being a Parasite, by Claude Combes, which sounds like a fun book to read if it shows up at my public library. (3/1: fixed that link/sorry 'bout that)

Midweek Mysteries on Myrtle

As a respite from wondering when the last of the erstwhile city council, Yes on 8, and sad Nader/Gonzales signs, left up for Veterans Day out of respect no doubt, will be removed from my surrounds, I had a look around the yard. I found two more unanswered questions there.

Both of these enigmas were found on the underside of myrtus communis leaves. This first image appears to be a parasitic wasp, a braconid, emerging from an egg it has parasitized. But on a second look the egg cluster really looks like a very tiny Polistes wasp nest or even waxy like honeycomb.

The second image is again what appears to be an egg mass. It was quite hard, not sticky or gooey, like a crust or lime deposit. Emerging from the "eggs" however are winged white somethings. If you know anything about insects you'll realize only adults have wings, and adults do not emerge from eggs (unless they are eggs of another species, parasitized). The shape of the buggies is really familiar to me but I am mystified, bamboozled and just cannot place what I am looking at here.

The Sharpshooter Phenomenon

You might interpret the title of this post as a shameless attempt to cash in on the Palin buzz and trick unaware completely-not-interested-in-bugs web surfers into reading my blog, but you'd be wrong. This post has nothing to do with moose, the NRA, teen pregnancy, earmarks or anything at all (known or more likely unknown) about that female candidate for vice president of the United States. I am a woman, though, hoping you'll just continue reading out of some sense of misplaced enthusiasm!

This post is about that pesky bug Homalodisca vitripennis referred to by the common folk as the glassy-winged sharpshooter, is a leafhopper in the leafhopper (Cicadellidae) family with strong leafhopper family values. In the ornamental garden these bugs usually do little damage and they are sort of cute in a homely way. Their non-threatening appearance disguises their potential to wreak great damage, since they are a carrier of a bacterial disease of plants. The sharpshooter sucks the juice out of a broad range of plants by inserting its mouthparts into the fluid-conducting xylem. While it's sucking, if it is harboring xylella fastidiosa bacteria on its mouthparts the disease organism can be transmitted to a new host plant. This organism causes Pierce's disease which could wipe out life as we know it here in California: that is, it kills grape vines at the base of our wine industry. It also kills nerium oleander, a nice evergreen shrub that we have learned to live without but miss dearly.

This summer I've seen more sharpshooters than has been typical, but I've also noticed them on more plant hosts than before. These opportunistic little buggers have been feeding on sunflower, abutilon, privet, citrus, artemisia, texas ranger, pittosporum, dodonaea, asclepias, elm, broom corn, senecio, acacia, pseuderanthemum, and even opuntia. Cindy has quite a gathering on a fern in her yard. They are expanding their feeding host base.

What about their egg-laying hosts? I've found egg masses on privet, dodonaea, the kumquat and broom corn. The eggs are inserted beneath the epidermis on the underside of leaves, and so can be hard to spot on thicker leaves especially. So, of course there could be egg-laying on other species of plants that I just haven't seen.

Some parasites are beginning to take hold within the sharpshooter range, including my yard. Tiny wasps in the genus gonatocerus lay their own eggs on those of the sharpshooters, which then hatch, parasitize and kill the host. I've photographed some egg masses to show the difference between a parasitized mass and one that hatched sharpshooter nymphs. The first photo is a parasitized egg mass, and shows the characteristic pinholes which are the exit holes of the emerging wasps. Lots of the egg masses I am seeing had pinholes, and this is the first year I've seen them. The second photo down is a dried up egg mass that hatched. You can see there are no pinholes. The third photo is a dodonaea leaf that was heavily used for egg laying, where the dead portions have dried up and fallen out. No way to tell if they had or had not been parasitized. I haven't actually seen the wasps; the photos and information at UC IPM are consistent with my observations and so I believe these are indeed the wasps at work.























So the sharpshooter population has increased and spread out, but their parasites has also begun to take hold in the little domain of my yard. Evidence of pest-controlling parasites such as these gonatocerus wasps is a compelling reason NOT to use insecticides in my garden and yours since the sprays kill the wasps as well as they might the target pest. By the way, there are also lots of leafhopper assassin bugs hatching recently, which prey on the sharpshooters. Its been my experience that parasites and predators are more effective at pest control than spray over the longer term, and it will be interesting to see how the glassy-winged sharpshooter population moves next summer. Perhaps homalodisca vitripennis is on the verge of control and the IPMers will be able to chalk up another biocontrol victory.

And why are they called sharpshooters? After they insert their mouthparts into the xylem stream the volume of fluid is such that they must excrete in order to allow more plant juice in. So they shoot the shit so to speak in order to keep feeding. You'll be standing unawares in the yard enjoying the day or looking for bugs or thinking about which presidential candidate to vote for when all of a sudden a droplet or perhaps several droplets of excreta hit you in the face. I don't know about you but I tend to go for the guy with the most science and the least excreta.