We have probably went to Albany Hill over a hundred times in just this year. Today was the last time. We took a bunch of photographs on the way, just to see how it will change by the next time we come back to Albany. A new segment has just been added to the Bay Trail this year with newly propagated willows (Salix) and alders (Alnus) along a man-made creek that mimics the rest of the trail perfectly. In a few year's time, we expect that it will grow in a lot. 

The following are pictures of the two blocks of the trail that have always been here. Most of the trees are really declining as the season passes, but it is still rich with life. 

At the end of the trail is Albany Hill. We did't see too much flying today, except for some skippers as detailed in here. We were not able to find any red admiral (Vanessa atalanta) larvae or eggs on the pellitory (Parietaria) even though the plants were getting clobbered in eggs all throughout the summer. 

After exploring the outside of the hill, we crossed the creek to get inside. The pipevine here was in pretty bad shape, but there were still a one or two pipevine swallowtail (Battus philenor hirsuta) larvae. A while ago we had come and found a least a dozen or two, so we suppose they either pupated or died. 

Inside the hill, the scenery was a far step from when we first came in the Spring. The ground was covered in yellow hay and the trees were mature and dry. To our surprise, we saw a single western tiger swallowtail (Papilio rutulus) at some point. We took this as an opportunity to take a few pictures of ourselves one last time before we leave (as you may have noticed, the pictures of us have changed on this website).

It has been a while since we stepped foot into Tilden, but we decided to go today because we only have a few days left. At this time of year, there aren't really any swallowtails around of any species in flight but to our surprise, we did still find a few pipevine swallowtail (Battus philenor hirsuta) caterpillars on the pipevine (Aristolochia californica) growing at the Nature Area's butterfly garden. Last year, they were basically completely gone by this time. It seems that only a few of them ever emerge to make the flight in August; the overwhelming majority of the larvae we reared in the Spring went into diapause. Admittedly, the pipevine at the garden was in very good condition with lots of new growth, perhaps after suffering from disease in the Spring that got it off to a late start, unlike the stuff at Albany Hill which also started growing earlier and got larvae earlier. 

After the garden, we went down a trail. There is a lake there, so a lot of the grass was still somewhat green and there is willow (Salix) and stinging nettle (Urtica dioca). Though not nearly as common as they were a few months ago here, we did across a western tiger swallowtail (Papilio rutulus) still flying this late into the season. We also found a satyr comma (Polygonia satyrus), but there was nothing on the nettles on the trail or at the garden (and strangely, no red admirals [Vanessa atalanta] either). 

After the lake, things get a lot more dry and it starts looking like a typical California landscape -- yellow grass everywhere with tons of tiny prairie butterflies hopping around. There were perhaps hundreds of blue hairstreaks there courting, nectaring, and just going about their business. They were probably all acmon blues (Plebejus acmon). There is also a lot of thistle (Asteraceae) in that particular area with very obvious frass filled silk nests by painted lady (Vanessa cardui) larvae, but we could not actually find any larvae (they must have already pupated).

A little past this segment, there starts to be less grass and more trees consisting mostly of live oaks (Quercus) and a few California buckeyes (Aesculus californica) and pines (Pinus). Here, the dominate species were California ringlets (Coenonympha tullia california) as well as some mylitta and field crescents (Phyciodes mylitta, pulchella) which were courting. There must have been a hundred of all of these too. 

On the way back, we past the lake again. There is a bridge there, but the water underneath it has apparently all dried up. The area is shaded with lots of green trees that we don't know, so no leps. 

After that, we hurried to the Tilden botanical garden which closes at 5 PM. Most of the pipevine there is in atrocious condition, about the same level as the pipevine at Albany Hill, except for the stuff growing right next the water which looked almost as good as Spring. There was nothing flying there whatsoever, but it was still a nice chance to explore some paths that we hadn't walked before. 

Pictures of pipevine swallowtails (Battus philenor hirsuta) in copula via hand-pairing.

We had a male emerged a few days ago that had one side of its wings completely crippled but the other side more or less okay. It probably came out of a deformed pupa because its abdomen is also misshapen. However, a female emerged two days ago so we decided to give him a go anyway.

These are quite difficult to hand-pair compared to the fluted swallowtails (Papilionini). Their genitalia is completely different. What makes is hard is that the males' clasper flaps are very small whereas the females' gentialia are very, very large. They allegedly also need to be paired from an acute angle a not across from each at 180. We have had trouble hand-pairing these in the past but surprisingly, it worked almost instantly this time. 

Our luck ended pretty quick though because at some point the female flew a bit while dragging the male (typical of all swallowtails in copula) and the male lost his grip. We tried multiple times to try to re-pair them but it wouldn't work. So much for that! I don't think we would have been able to get eggs out of the female anyway because we don't have any good pipevine (Aristolochia californica) and even if we did, we wouldn't be able to raise the larvae for the same reason.

Pictures of pipevine swallowtail (Battus philenor hirsuta) and anise swallowtail (Papilio zelicaon).

Another very small pipevine swallowtail (Battus philenor hirsuta) emerged today, most likely from a late non-diapausing pupa. It was a female which we haven't had a chance to get any good photographs in the past. Unfortunately, pipevine swallowtails are probably some of the hardest things to get to stay still because of their weak legs. It fluttered about and eventually flew away after two poor shots. 

We also had several female anise swallowtails (Papilio zelicaon) emerge over days but have no males. We released three females today and after about half an hour we saw one of them come back, nectaring on some flowers. It eventually landed somewhere and we got a quick shot in. It is a very yellow individual -- almost orange in some cells -- typical of summer broods. 

​Authors
Brian Liang

Male pipevine swallowtail (Battus philenor hirsuta) pictures.

Today, we had a very small male pipevine swallowtail (Battus philenor hirsuta) emerge. It was almost definitely one of the last ones we caught (probably as a last instar larva in the wild) that probably didn't diapause. All of the other pupae we currently have, dating back months ago in May are far overdue and are probably not going to emerge until much later this year or the Spring of next year. 

This guy was very pesky to photograph. These pipevines have very weak legs compared to fluted swallowtails (Papilionini) that just don't seem like they are meant to crawl. . . as a result he kept dropping or fluttering around. Also unlike the fluted, he simply would not open his wings all the way and instinctively kept them closed, probably because the aposematic pattern is on the hindwings. 

Today is our birthday so we decided to go to the University of California Botanical Garden. Also, admission was free today. 

The first thing that we saw there were pipevine swallowtails (Battus philenor hirsuta). We had thought that the botanical garden at Tilden was pretty crazy but this place was even more crazy, which is especially surprising considering that the first large flight is over. We probably saw dozens of them in just a few hours. Most of those that we saw were males, but there were definitely still a females. The funny thing was that we could barely find any pipevine (Aristolochia californica), except for a few new plants. And on these, we only found a single instar larva and no eggs. Interestingly, there was a humongous Aristolochia macrophylla but it didn't have any inhabitants in any form. 

We also saw a few other butterflies like western tigers (​Papilio rutulus). Unfortunately they were all males from what we saw, and there weren't a whole lot of host plants there. It would have been illegal to catch anything there anyway. We also saw a male pale swallowtail (Papilio eurymedon) as detailed here and the following nymphalid that we can't identify.

We also saw this hopper that darted out when we stepped near it. It is a pallid-winged grasshopper (Trimerotropis pallidipennis) which are extremely common in our region. 

We found parasites both in our wild-sourced pipevine swallowtail (Battus philenor hirsuta) pupae and in an anise swallowtail (Papilio zelicaon) larvae. 

When catching stuff directly out of the wild, especially larvae and pupae, the obvious risk is parasitism. Last year, we discovered over half of our pupae that resulted from wild collections of pipevine swallowtail (Battus philenor hirsuta) late instar larvae from the Berkeley Hills to be parasitized. This year, we have been primarily rearing the larvae from eggs so most have been safe thus far, but just recently we did also collected a handful of last instar larvae in the Berkeley Hills. Needless to say, some of the more recent pupae have been turning up dead (hollow) with uneven red splotches on the backside. It is always this same type parasitoid. 

When we opened up one of the infected pupae yesterday, we took a while before we were able to fish out the culprit since it was so small. Most likely, had we not dug it out it would have spent a good number more days inside the pupa feeding. Last year we also noted that the parasitized pupae did not die immediately and the maggots took a very long to come out if they did at all. This suggests that most larvae are only ever parasitized when they are near the end of development and that the majority or all of the maggots' growth occurs in the pupa. 

As a follow up, today we found one of our wild caught (somewhere in the city) fourth instar anise swallowtail (Papilio zelicaon) larvae that was also parasitized. Despite catching probably hundred of larvae over the years in various stages, we very rarely see parasitoids so it's still a surprise when it does happen. The parisitoid is this thing that always comes out in the third or fourth instar and spins a small golden colored cocoon. 

Today we witnessed a pipevine swallowtail (Battus philenor hirsuta) laying an egg cluster on California pipevine (Aristolochia californica) at Albany Hill (Albany, California).

It really takes a person to go checking every day in order to see a moment like this. Today, we were lucky enough to witness a female pipevine swallowtail (Battus philenor hirsuta) choosing a spot on the ground and laying eggs on a small, growing shoot of California pipevine (Aristolochia californica).

​We had seen the butterfly nectaring when we first got to Albany Hill, which was an interesting sight.​ We instantly recognized her as a female by the drab coloration on the front side of the forewings. 

About an hour later, she was still flying about around the pipevine. It was obvious that she was laying or intending on laying eggs there, and eventually she landed on the ground and waited for several minutes, touching the vine and twitching the ovipositor. Most females will spend hours investigating different shoots, landing on them but then leaving, but it appeared like she had for-sure chosen the right spot here. After a while, she very quickly laid a set of eight eggs over the course of about two minutes. The entire time she sat there, not flying out after each egg or really flapping the wings. 

The freshly laid eggs are interesting. After collecting so many egg clusters, we have never actually seen how they look like immediately after being deposited. The eggs look slightly wet and smooth because the grainy substance coating them hadn't dried yet. These particular eggs were also very orange and pale rather than bright red, possibly because the coat that gives them the red color was not dried or due to variation caused by genetics because we saw another cluster, discovered yesterday, that was orange but appeared to be dried. We also speculated that older females have less of the red substance and laid smaller clusters such as this one. 

​After we looked around, we discovered many egg clusters and groups of young first or second instar larvae that we hadn't before because they were all located so close to the ground. Last year during June, we also recall finding most of our eggs near the ground in the Berkeley Hills. It is likely that this is a common trend for the later season flights because this is where many of the new shoots/plants, now an extremely scarce resource, are located. 

One of our pipevine swallowtail (Battus philenor hirsuta) chrysalises from this Spring eclosed into a beautiful male.

The diapause pattern of our California pipevine swallowtail (Battus philenor hirsuta) is especially strange. There is evidently more than one flight each year, but consistently we only have a few pupae emerge during the same year from each brood, some of which do so far after then they should have. Today, we had only our third emerge, the first male, of over 50 pupae we saved from earlier this year. The fella has brilliant iridescent blue front hindwing scales. 

The particular pupa was decently sized (as were most all of the earlier pupa) but the butterfly was not particularly large in terms of wingspan. Clearly, pipevine swallowtails have a much lower wingspan to pupal weight ratio than the other swallowtails. The abdomen, however, was quite enormous for a male and rounded in shape rather than thing and pointed as in Papilio​. ​

It is evident that the first brood of pipevine swallowtails (Battus philenor hirusta) is now ending here.

Despite the haphazard diapausing pattern of our "California" pipevine swallowtails (Battus philenor hirsuta), their broods are still fairly distinct. Starting as early as February, the first largest flight of the year begins and peaks sometime around April. By the start of June, for a brief moment there are few adults or eggs being laid and the first brood is usually ending. Then, simultaneously, the second flight begins and eggs are once again seen alongside last instar larvae and recently formed pupae. 

Today, when we went into the Berkeley Hills (Berkeley, California) to check on the status of flight, we found hordes of last instar larvae. More than half of the larvae we found were in this stage. The youngest larvae we found were mature third instars. We only found a single egg cluster, either laid by a first flight straggler or by an early second flighter. 

This is consistent with what we observed last year at this time. Many of the larvae look just about ready to pupate and, undoubtedly, many of them already did before we got there. At the same time, we are suddenly seeing a lot of fresh eggs being laid at Albany Hill. . .

What we also noticed was how much the pipevines (Aristolochia californica) had declined overtime and how overcrowded they were with larvae. We found a number of late instar larvae that were evidently disease with symptoms identical to what we have seen from our own home rearing. The larvae stop eating and just crawl around or sit there as they "liquify", eventually become completely flaccid, and die. Two years ago in August, we also found larvae like this.