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Third Diapausing Anise Swallowtail Ecloses

2/28/2017

Our third anise swallowtail (Papilio zelicaon) of this year eclosed after a winter diapause.

2/28: Despite releasing this individual yesterday, we found it perched in a shaded spot on the ground today unable to fly due to the cool weather so when the sun came out, we placed on a sunny spot and it promptly flew away; below is another photo of it, this time posed on fennel.

2/27: This individual was released; can be seen below posing on Ceanothus

2/26: Another male anise swallowtail (Papilio zelicaon) eclosed today. It is the third to break diapause this year.

- Alan

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Samia ricini L5/L6/Prepupa/Cocoon Rearing Notes (2/6/17-2/26/17)

2/26/2017

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Rearing notes for our fifth instar, supernumerary sixth instar, and prepupal eri caterpillars; and eri cocoons (Samia ricini). These are offspring of Europe sourced sibling-paired adults from a previously reared brood and have been reared indoors on citrus (Citrus).

Rearing Notes 2/6/17-2/26/17:

2/26:

The pupa from the opened cocoon is almost fully tanned, but unusually the wing cases look like they well not expand to fill the pale fleshy area
We decided to cut our oldest pupa and it turned out to male (second row, left photo); this pupa's wing cases look properly expanded but one of the antenna is bent at an odd angle
We cut a large cocoon that we suspected was female, and it was (second row, middle photo)
Comparing the male and female pupae, the female pupa has a slightly larger abdomen but otherwise there is no difference (even the antennae are the same size); however, they can be sexed by inspecting their gonophores (a slit like indentation on the ventral tip of the abdomen) - the female slit cross through the fourth and fifth segment after the wings while the male's is contained on the fifth; also, the female's fifth segment merges with the fourth while the male's segments are well defined and bears kidney shaped bumps

2/25:

The prepupa in the opened cocoon pupated this morning; the teneral state is very bright translucent colored and soft - the ventral side is mostly translucent yellow while the dorsal side is mostly golden brown and the abdominal segments have blue marks where the prolegs used to be
By evening, the pupa had tanned into a golden brown on the ventral side and a rich reddish brown on the dorsal side; the proleg marks are still there but are slightly fainter; strangely, the wing cases have not expanded over the fleshy translucent yellow portion on the ventral side yet
The pupa is male because the fifth abdominal segment after the wings is well defined (not merging with the fourth segment after the wings) and bears two kidney shaped bumps ventrally

2/24:

The prepupa in the opened cocoon has dulled significantly and become soft and loose skinned with a very clear pulse; it is very close to pupation

2/23:

Finally decided to count up all the cocoons and detach them from leaves since it's been getting crowded in the container we've been letting the larvae spin in; we currently have 32 cocoons with many more to be produced; most weigh around 1.3-1.5 g which is quite small; once we are sure the larvae inside have pupated we will get an official weighing of all the cocoons
A few of the cocoons are extremely thin probably because the larvae were disturbed and ran out of time to finish spinning before becoming immobile; one failed to build a cocoon and only made a few strands which is shown in the fourth row of photos; most cocoons have a pretty large and distinct escape hole at the top; the larvae's body is oriented so that the head is facing the hole
We decided to cut open one of the older cocoons that still has a not-yet-pupated larva in it (fifth and sixth rows of photos); this prepupa is close to pupation based on the firmness and color of the body, as well as the flaccid scoli; it is only about 2.5 cm now and weighs 1.2 g while one of our largest sixth instar larvae is 5.5 cm and weighs 4.2 g; the preupa's body is compact and very saturated in color, giving it a green and yellow color with vibrant blue scoli, though the head capsule and thoracic legs have dulled since they have mostly dissolved internally

2/22:

Sixth instar larvae are becoming quite large; most are 3-3.5 g and the largest is 4.1 g
Many larvae have developed black sooty spots on their tubercles ever since offering them fruit, and appears to be some sort of disease due to the bad sanitation, though not fatal; those heavily infected have their tubercles completely "melted" down to the base, leaving a black burnt looking spot

2/21:

Fruit seems to be a good source of water for the larvae but otherwise adds little to their diet; many of the small fifth instars that have trouble taking on mature leaves are beginning to rely more and more on the fruit and yet they are growing much despite consuming quite a lot of it; the sixth instars on the other hand feed mostly on leaves but also feed on the fruit for water once in a while which seems like a pretty balanced diet

2/20:

Sixth instars making good progress; most already 3+ g and still have a good amount to grow; generally much healthier looking than the normal sized fifth instars as well

2/19:

Larvae could tolerate high acidity of lemon fruit, though we switched them back to tangerine because the lemon juice causes worse sanitation problems due to its higher viscosity

2/18:

Offered larvae lemon fruit

2/17:

Supernumerary sixth instar larvae are much more tolerant of mature leaves than normal fifth instars; likewise, they are growing at a much better rate and look healthy and plump ; the largest is already 3.5 g which is almost the size of a full grown normal fifth; though the weight may be slightly exaggerated because the individual had clearly been feeding on a lot fruit and carried a lot of water weight
We are regularly providing fruit for the larvae as they seem to be doing quite well on it; larvae that have been feeding on it for a long time have gained a faint pink or orange undertone, especially on the thorax
Many cocoons are starting to collect up; there have been at least one new cocoon spun every day so far

2/15:

Larvae seem to have enjoyed feeding on tangerine fruit so far, eating whole slices of it; today we offered them some grapefruit as well though it may be too acidic (if it is a problem)

2/13:

Quite a few cocoons now

2/12:

The larvae seemed to do well on the citrus fruit though the peels were not so good and the juice created a lot of excess moisture that made the sanitation bad
None of the purple-leaf plum blossoms were eaten
Four more became prepupae today, one of which is 2.7g after having runny frass which isn't that bad; total of nine prepupae/cocoons now

2/11:

Already over 30 supernumerary sixth instars, all of nice size; unfortunately, quality citrus leaves are harder to get than ever so pulling them through this extra instar is going to be difficult; we experimented around by giving them some tangerine peels and flesh which they readily ate, though we will likely only be able to do this once in awhile since they simply can't live off the stuff; we also offered them some purple-leaf plum (Prunus cerasifera 'Krauter Vesuvius') blossoms since they are supposed to accept Prunus, but so far none of them have eaten it, either because they are unwilling to switch hosts or they do not want to feed on blossoms

2/10:

The two finished cocoons are now 1.6 and 1.8 g respectively which still isn't horribly small, especially if they are males, though still below average mass
The two unfinished cocoons are starting to look quite round rather than oval and both are using the bottom of the container as an attachment point rather than leaves

2/9:

The first two prepupae have nearly finished spinning their cocoons; interestingly, now that the silk has begun to hardened, they appear just a slight bit tanner than the ones from last brood and are much smaller in volume, though when one was removed from the branch, it surprisingly weighed 2.0 g which is just under the average 2.1 g from the previous brood, though it will likely drop a a few decigrams by the time it actually pupates
Several small fifth instars molted into sixth instar and are much larger than normal sized fifth instars, being between 1-2 g while most normal fifth instars molted to around 1 g; the supernumerary sixth instar appearance looks almost identical to that of normal sized fifth instars which is expected, though they are greener with more saturated tubercle colors (a more mature look probably due to having slightly lower JH levels than that of a freshly molted normal sized fifth instar)
Despite their larger mass, the sixth instar head capsules are only slightly larger or the same size those of normal sized fifth instars (just over 4 mm in width); however, their shed fifth instar head capsule exuviae is significantly larger than the analogous normal sized fourth instar head capsule

2/7:

Both prepupae are almost finished with their cocoons which are small and compact unlike those from previous broods
Another larva became a prepupa and dropped to a very small 2.1 g

2/6:

The two prepupae have begun to spin silk; one of them had dropped to 2.4 g when weighed at night
New peak L5 larval mass for this brood at 4.3 g obtained by the individual measuring 5-6 cm in the photo
As expected, several small fifth instars entered apolysis for a supernumerary sixth instar; to clarify, these are not fourth instars mistaken for fifth instars, but rather, very small fifth instars due to the poor host plant quality that require an additional instar in order to complete larval development
Above are comparisons between a normal sized fifth instar and the very small fifth instars destined for sixth instars; surprisingly, their capsule sizes are quite similar in size, with the normal sized fifth instar's just over 4 mm and the small fifth instar's just under 4 mm; in terms of mass, however, the normal sized fifth instars are 3-4 g while the small fifth instars are only 1-2 g, which is actually very large compared to the mass of a full grown normal sized fourth instars that weigh 0.9-1.1 g; thus, despite being abnormally small initially, the small fifth instars should produce larger than normal adults since they will enter the sixth instar at a much larger size than a normal sized fifth instar

- Alan

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Poanes melane Rearing Notes (1/28/17-2/25/17)

2/25/2017

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Rearing notes for our umber skippers (Poanes melane). These were found as eggs and reared on Bermuda grass (Cynodon dactylon).

Rearing Notes 1/28/17-2/25/17:

2/25:

Another eclosed

2/23:

Another eclosed but is slightly crippled (mid and right photos); non-crippled one from yesterday on left

2/22:

Another eclosed

2/14:

Released the four most recently eclosed adults

2/13:

Two more eclosed

2/10:

A male eclosed

2/6:

Another female eclosed and expanded its wings properly

2/1:

Another female eclosed; as this is the fourth eclosion already, it is likely none of the remaining pupae are in diapause and will eclose soon as well; unsure if the pupal stage is not the overwintering stage for P. melane or if it was simply indoor rearing conditions of the larvae that induced non-diapausing pupae

1/30:

Another female eclosed; wings slightly bent

1/29:

A female eclosed and was released

- Alan

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Botany Notes (2/25/17)

2/25/2017

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Because the seasonality of insects is ecologically linked with the seasonality of plants, we record prevernal plant growth to estimate when to expect certain insects and familiarize ourselves with useful Lepidoptera host plants.

Cherry plum (Prunus cerasifera) - more blossoms; leaf shoots are vigorous and have enlarged
Purple-leaf plum (Prunus cerasifera 'Krauter Vesuvius') - in full bloom; branches already densely covered in small leaves and will be in full leaf soon
Lilac (Syringa sp.) - buds continue to enlarge and become purple
Fennel (Foeniculum vulgare) - extremely vigorous new leaf growth after just two weeks since pruning to base; main use of this plant is to attract and host Papilio zelicaon
Willow (Salix sp.) - branches covered in small vigorous leaf shoots and catkins; these willows have historically been very extremely vigorous and quick growing so should be in full leaf soon despite breaking dormancy just this week; can be useful for various tree - feeding lepidoptera such as Smerinthus sp., Hyalophora cecropia, Papilio rutulus, etc.

- Alan

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Found a Monarch

2/23/2017

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2016 was one of the biggest monarch years we had witnessed in a long time - individuals of all stages were seen frequently in every month of the year despite that they should be absent during the spring and summer months. However, during the fall and winter months when they normally are supposed to be quite abundant here, there were actually very few. We found no eggs or larvae on our milkweed when we normally were able to find dozens in previous years.

Strangely, today which is already very late in the season, we found a single fifth instar wandering around our milkweed. We decided to let it be and live a natural life (or death) rather than take it in to rear since there is no risk of predation by paper wasps (Polistes dominula) at this time of year so it should be fine if its made it this far already, unless it has been parasitized by tachnids in which case nothing we can do can save it. It'll probably pupate in a few days anyway so no point rearing.

- Alan

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First Signs of Trees Breaking Winter Dormancy

2/21/2017

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Deciduous trees in Albany, CA are beginning to show signs of breaking winter dormancy.

We don't usually write about anything other than insects on here (it's an insect blog after all), but since botany and entomology go pretty much hand in hand, it doesn't hurt to talk about plants once in a while. Because most insects are herbivores, the seasonality of their life cycles correlates strongly with the seasonality of plants. Thus, we always make sure to keep a good eye out for when the trees begin to break winter dormancy and plants begin to grow again so we know when to expect certain insects. Here in Albany, CA (and much of the state), the winters are extremely short and relatively warm, and thus trees begin to grow as early as February unlike most other places in the country where you usually have to wait until April or May.

Plum trees are usually the first of the fruit trees around here to bud, opening hundreds of blossoms in the course of a week or two followed by leaf growth. Just a week, our cherry plum tree (Prunus cerasifera) was only just starting to get flower and leaf buds all over its branches, and now it is covered in blossoms and leaf shoots. Once the blossoms fade, we can expect it to be green in a few weeks for our cecropias to feed on.

Some other trees in our backyard that are breaking dormancy are our rose (Rosa sp.) and lilac (Syringa sp.), which had no traces of green two weeks ago. Rose grows quickly and will probably be nice and bushy in a couple weeks. Our lilac tree is quite small and hasn't done very well in past years (it hardly bloomed last year), but this year it looks like it has a lot of buds that are budding and will probably open in the coming weeks.

Our lemon tree (Citrus limon) has been heavily pruned this year despite that citrus trees shouldn't be pruned much, simply because it is a very old tree and was becoming unhealthy so we wanted to reinvigorate it. Citrus trees are tropical and subtropical plants so they grow in response to rainfall changes and not temperature changes, but since this time of year also happens to be the rainy season, you can see the tree is beginning to grow and has several new shoots. Lemon tree shoots typically have a high concentration of anthocyanin which gives them a purple color while most other citrus are just green.

We also have two apple trees (Malus sp.) in our back yard, one of which is quite large and vigorous in the summer while the other is sort of scraggly and only moderately vigorous. Right now both appear dormant with no signs of green, though it is possible that the buds are enlarging but we're not quite sure. Historically, they should start blossoming in March and have leaves by April, so it's still a bit early. However, it has been an especially cold and overcast February this year which may cause they to blossom a few weeks later than usual, but we'll see. Hopefully they will be ready in time for our cecropias which we anticipate to hatch some time in late March.

- Alan

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Indian Walking Stick on Common Ivy

2/16/2017

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While pruning our trees today, we were very surprised to find a fifth instar Indian walking stick (Carausius morosus) on Common ivy (Hedera helix). It was intermediate green and brown morph. Though our C. morosus stock was originally started from wild caught specimen six or seven years ago when we were able to find dozens of young walking sticks on Dahlias (Dahlia) every fall, the wild population has seemed to become quite sparse for the past several years as we only ever find a few each year now which is why this was a surprising find.

- Alan

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Another Anise Swallowtail Ecloses

2/13/2017

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Another male Anise Swallowtail (Papilio zelicaon) eclosed today and was released.

- Alan

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Found a Rough Stink Bug

2/13/2017

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We found a rough stink bug (Brochymena sp.) that has likely just broken diapause.

These rough stink bug adults show up on our trees every year around late winter and early spring. and we often find their pearly white egg clusters around this time too. We are not positive about the species identification of this individual except that it is in the Brochymena genus, probably either affinis or sulcata based on our region. The adults overwinter in tree bark and come out to lay eggs once the weather warms, so it is very likely that this individual has recently just broken diapause as it has been fairly warm this week. As we are not Hemiptera experts, we do not plan on rearing these.

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Taking Cecropia Cocoons out of Cold Storage

2/11/2017

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We have taken our cecropia cocoons (Hyalophora cecropia) out of cold storage in order for them to break diapause.

We plan to rear of cecropia caterpillars starting in April this year, right when spring starts and when the trees are most vigorous. Thus, in order to time this event, we took our eight remaining live cocoons from last summers brood out to break diapause and eclose at the end of this month. We then expect that it will take about a week to get all the pairing and eggs, and another two weeks for the eggs to hatch, at which time spring will begin (March 21). Though spring rearing is definitely too early to be rearing Saturniids in most parts of the country (and this particular H, cecropia stock certainly would not be in flight until several months later in their native New York), here in northern California, the cold season is mild and short meaning it should be warm enough by this time. We plan to use apple (Malus) and plum (Prunus) again this year, and perhaps other host plants if they leaf up soon enough, as these worked quite well last year for the non-diseased portion of the brood. Recently we have been pruning back some of these trees in order to make them more vigorous in preparation for spring and rearing.

Update 2/11: we weighed all eight cocoons to make sure they are all alive and based on mass. they should be since most only lost a few decigrams. Also, the pupa in the 4.6 g cocoon moved around a lot when we weighed it.
Cocoon mass (g): 4.6, 4.9, 5.4, 5.6, 7.1, 7.5, 8.1, 8.2

Mean: 6.43
StDev: 1.46
Median: 6.35

- Alan

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