Field Season 2012

This summer I am replicating a few things that I have done over previous summers. First, I am running another field experiment with pastry caterpillars similar to the work I did in the summer of 2010. That work resulted in a nice paper and was recently published in Animal Behaviour (see manuscript here). In addition to this, I will be rearing Papilio canadensis caterpillars from eggs laid by wild-caught females to repeat what I did last summer (2011).

As I explained in an earlier post, you need special authorization to collect Papilio butterflies in Ontario. I have approval to collect 20 Papilio canadensis butterflies. I haven't had much success trying to hand-pair wild-caught Swallowtails, but I did have some success inducing wild-caught females to lay eggs in captivity last summer. So, this season I'm only focusing on females. Males and females not only look different (see earlier post on sexing), but they behave differently. Males are usually seen patrolling for females along flyways lined with their host plant (Trembling aspen, Populus tremuloides), or sometimes "puddling" in a group of other males. Females on the other hand don't puddle, and are really only encountered around nectar sources. Basically, if you see a swallowtail flying quickly along a tree line or puddling its probably a male, if you see one fluttering slowly around a flower its probably a female. The flight season for Papilio canadensis typically ends mid-to-late June so I have to move quickly if I am going catch gravid females.

I have been out a lot this past week, and I had only seen males. All the prime nectar sources from last year either weren't flowering or had been cut back. Today after patrolling my usual sites and coming out empty-handed again I decided to explore new areas. Well, it worked, and I can tell you that I was pretty relieved.

Papilio canadensis female - first female of 2012!

The first 2 came in rapid succession, I caught the first feeding on the flower below and after I tucked her away safely another came to visit a flower just feet away from where I caught the first. The is the flower that they were feeding on:

I'll try to remember to look up the name of the flower, or if you know just post it below in the comments! After doing some more exploring I found an even bigger patch of these flowers and I caught a third female.

Nectar patch a great collecting spot for female P. canadensis

Similar nectaring patch to the one above, just a few meters away from it.

I sleeved these three females over live saplings of Trembling Aspen and I will feed them tomorrow.