What You Can See in Two Hours at Tilden

In just two hours on our hike at Tilden Regional Park (Berkeley, CA) encountered at least 8 different species of Lepidoptera including the Pipevine Swallowtail (Battus philenor), Western Tiger Swallowtail (Papilio rutulus), Common Buckeye (Junonia coenia), California Sister (Adelpha californica) Painted Lady (Vanessa cadui), Red Admiral (Vanessa atalanta), Cabbage White (Pieris rapae) and the Acmon Blue (Plebejus acmon). 

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As you have probably read in our other recent posts (here, here, and here), we went to hike on one of the many trails at Tilden Regional Park today because we have just received our brand new butterfly net. As an overview, Tilden -- like much of this part of California -- is basically a dry woodland (lots of trees and dried grass) but with some creeks to provide riparian habitat which some species prefer. Now we'll cut to the chase and just discuss some of the butterflies we today.

When we first got to Tilden, we saw a Painted Lady (Vanessa cadui) flying around some Redwood trees (Sequoia sempervirens) and bramble (Rubus ursinus). It was flying too fast to catch, but we did end up finding two Painted Lady caterpillars on milk thistle (Silybum marianum) later, when we actually started on one of the trails. A common species, yes, but not especially around here with the smaller West Coast Lady (Vanessa annabella) usually dominating the scene.

Before we got onto the trail, we first went to check out Tilden's butterfly garden. The naturalists at Tilden are pretty smart and they have some legitimate butterfly experts working there so the garden was pretty good. It has plenty of excellent butterfly nectar sources (the full list can be seen on their brochure) and some caterpillar host plants as well. When we got there, we saw two Pipevine Swallowtails (Battus philenor) around the California Pipevine (Aristolochia californica) but we must have startled them because they quickly flew up into the trees to roost. We also saw a Red Admiral (Vanessa atalanta) flying around the area but, like the Painted Lady, it was just too quick of a flyer (they move in quick fluttering spurts instead of easy glides like some swallowtails and Monarchs [Danaus plexippus]). 

When we finally arrived on the trail, the first butterfly we saw were Common Buckeyes (Junonia coenia) all along the dead grasses, sunning themselves in the hot mid-afternoon sun. They were probably all males since the females of the species rarely show themselves unless they are around the host plant laying eggs, but we went for it anyway and caught five out of more than ten that we saw that day. We have never even seen the eggs or caterpillars of this species in real life despite them being so extremely common in dry, open areas like this (good examples are Albany Hill and the Ohlone Greenway) where there is an abundance of plantain (Plantago, a potential host plant). The second most common butterfly around these places is definitely the introduced pest, the Cabbage White (Pieris rapae), and you can bet that we saw plenty of those as well.

In the same little clearing where we saw our first Buckeyes, we also saw a majestic Western Tiger Swallowtail (Papilio rutulus) gliding along the tops of some Eucalyptus trees (Eucalyptus). But it was just too fast and too high up for us to even think about catching it. By the end of the two hours, we had seen at least three or so of them and weren't able to catch a single one. 

While we were catching the Buckeyes, we also happened to step into a little patch of dead grasses where there were tons of Acmon Blues (Plejebus acmon) chasing each other around in aerial battles. We didn't try to catch these and they were probably all males as well anyway by this behavior. However, they were the only one of the seven identified butterflies we saw today (there were a bunch of other little gossamer-winged butterflies [Lycaenidae] and other brush-footed butterflies [Nymphalidae] like checkerspots but we didn't get a long enough look to identify them) that we got pictures of since they actually stopped long enough on the ground. 

The last butterfly we saw today was the California Sister (Adelpha californica). Like all of the other species, they are not uncommon around here but this was our first time really seeing one up close. It stopped to nectar for a very long time but we weren't able to catch it or take any good photos because it was too far into the vegetation and we would have to cross a strip of spiky bramble to reach it. 

In conclusion, it was a great day for butterfly sightseeing. Lots of beautiful species that we don't often encounter in the city. If only we could have caught a few and gotten pictures of them all. Perhaps next time. . .

- Brian