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. 

Anise swallowtails (Papilio zelicaon) courting on 6/29 in a school garden in Berkeley. We were trying to capture the male, a rather small and flitty individual, for possibly an hour before the female came in and they eventually disappeared. In the process, the male basically just helicopters from side to side over the female who, in this case seemed reluctant and kept jumping away from the male every time he approached. 

We also saw a mylitta crescent (Phyciodes mylitta) nearby in the same garden. It happened to land and was very calm for several minutes while we photographed.

At Albany Hill we can probably see about a dozen different common buckeyes (Junonia coenia) every time we come, darting around annoyingly. We saw a pair courting today where the male landed right next to the female and followed at her tail each time she moved. We caught the two easily and tried to see whether it was possible to hand-pair these. It did not seem doable after taking a look at the males tiny and rather hidden genitalia. Below is the male of the pair. 

Today was the first day of some decent sunshine this whole week, and we didn't feel like collecting more pipevine eggs in the Berkeley Hills anymore since we have so many already, so we decided to spend the afternoon at Albany Hill. As long as there is reasonable sunshine, there are always Papilio rutulus flying along the willows there during the Spring and early Summer; today was no exception. While walking on the path at the bottom of the Hill, we spotted many of the swallowtails flying up high, most likely all males, and we managed to net one when it came down low. 

The netted rutulus was a small, very yellow male with nice, triangle wings, and was in perfect condition except for a small break on one of the tails. We normally don't get many shots of the rutulus we see here at the Hill because we don't want to risk them flying away when we set them down on a plant to photograph. However, we decided we really don't have any use of males anyway, so we this time we just let it go and took some nice photos of it before it flew away. 

Unlike the previous trips we have had at the Hill this year, the grasses along the path were filled with Myllita crescents (Phyciodes myllita) basking in the sun and nectaring on small flowers. The larvae of the showy little butterflies feed on thistles, though we've never been able to find any.

Today we took a short hike in Tilden Regional Park until we were just past Jewel Lake. There, we witnessed a completely different selection of butterflies than what we saw last summer in July. The first thing we saw was  west coast ladies (Vanessa annabella) and painted ladies (Vanessa cardui) which seem to be in large numbers during this time. These were mostly flying around tall grasses and nectaring. We also saw a male sara orangetip (Anthocharis sara), which is a species that we have never seen before. This is probably one of the only times that we have seen a pierid around here besides the cabbage white (Pieris rapae​) which we also saw on the way back. Also out of random chance, we also found a mylitta crescent (Phyciodes mylitta) and something that we cannot identify but looks vaguely like a some sort of Lycaenid. Both were flying among dead grasses and little weedy nectar plants away from the creek. 

We also observed one or two western tiger swallowtails (Papilio rutulus). One was around the butterfly garden which is right beside the creek while the other one (it could have been the same one) was flying along the creek past Jewel Lake. They flew by too quickly to distinguish either by physical characteristics or by behavior whether they were male or female. Despite not seeing any eggs, we also saw a single pipevine swallowtail (Battus philenor hirsuta) near pipevine, though we also could not tell if it was a male or female. 

​​Authors
Brian Liang

Today we caught a Mylitta Crescent butterfly (Phyciodes mylitta) by hand while it was nectaring!

Our region here in the bay area is filled with small weedy butterflies like the Mylitta Crescent. With about a one-inch wingspan, this common brush-footed butterfly (Nymphalidae) is very difficult to find in the caterpillar stage. Other little butterflies like skippers (Hesperoidia) and lycaenids (Lycaenidae) are equally difficult to find despite the enormous abundance of the adults. Most feed on obscure little shrubs and weeds. The Mylitta Crescent is supposedly a monophagous feeder of thistle, a very common and less obscure weed around here but we still have never found any of their caterpillars of eggs. 

Today we found a Mylitta Crescent nectaring in somebody's garden. This is the easiest time to catch a butterfly. We didn't even bring a net and just grabbed it off the flower by hand. The following are some pictures.

- Brian