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This rare beauty has previously only been known from scattered localities across the mountain west and only from a few individuals every other season. That is until Denver Museum volunteer Barbara Bartell began inventorying moths on her property near Golden Gate . . . → Read More: Monday Moth]]> To reignite the Monday Moth series here is a stunner: Melemaea magdalena (Geometridae).

This rare beauty has previously only been known from scattered localities across the mountain west and only from a few individuals every other season. That is until Denver Museum volunteer Barbara Bartell began inventorying moths on her property near Golden Gate Canyon State Park in the Rocky Mountain front range. Over 8,000′ these moths turn out to be a regular visitor at her cabin blacklight and we now have the largest series known of this stunning species (and all perfectly curated!).

Leave it to Denver to combine two things perfect for this blog – entomology and skepticism! If you haven’t seen these clips then take a second to watch the video above. At the very least this appears to be a real phenomenon, camera crews from the news station were able . . . → Read More: UFO Swarms Over Denver]]>

Leave it to Denver to combine two things perfect for this blog – entomology and skepticism! If you haven’t seen these clips then take a second to watch the video above. At the very least this appears to be a real phenomenon, camera crews from the news station were able to record the very same effect. So what could they be?

I had an instantaneous recognition of what these UFOs were – flying insects, probably flies of some kind (Diptera) mating in the warm afternoon sun. It has been nice here in Denver and the hours around 1pm are always the warmest (strangely the same time the “UFOs” are most active). But it’s hard to tell with any degree of certainty what these objects are because of the way that KDVR shows the clips. Odd angles, 2 second flashes, fast forward, super slow motion, super contrast… you only have fractions of a second to see the clip in real time. But when you do it seems so very obvious – and in my professional opinion – that these are insects.

Unfortunately they now have a quote from a Denver entomologist, Mary Ann Hamilton (misspelled as Mart on the KDVR website), saying these are not insects. Facepalm. I don’t know Mary and I certainly can’t blame her for being uncertain as to what these are after staring at the footage over and over and over again. In my opinion it was too hasty to rule out insects. Especially because once you enhance… enhance… and ENHANCE the footage you being to lose all track of reality. The camera footage has recorded very out of focus insects, and the very nature of optics means you have lost most of the information outside of the depth of field. And so enlarging and slowing down these images only makes this problem infinitely worse. The pixels become too large to render any meaningful information and an effect known as pareidolia starts to kick in.  Our brains start jumbling together often meaningless data into something recognizable. This is why people see a face on Mars, or rocket boosters coming out of the butts of these insects flying over Denver. And I don’t blame Mary for looking at some of these shiny objects whipping around in weird directions and not seeing insects. But perhaps KDVR could have requested an interview with someone at the Denver Museum (which they did not) – they would have been given an entomologist with much more field experience. I can’t say Mary is unqualified and I don’t mean any disrespect to her, but I don’t believe running a butterfly house is the same thing as being an active research entomologist.

This video is pretty excellent for explaining insect UFOs – although these are much larger insects than the ones captured above Denver.

And check out this cool video of a Syrphidae fly hovering in the sun – imagine these out of focus and hurtling around in front of the camera…

The local news for most of the eastern US and Canada has been aflutter (ha) recently with reports of the irruption of Vanessa atalanta – the Red Admiral butterfly.  While this is a common occurrence every spring for these butterflies to migrate north from their overwintering grounds in the southern US, . . . → Read More: The Invasion of the Butterflies]]>

The local news for most of the eastern US and Canada has been aflutter (ha) recently with reports of the irruption of Vanessa atalanta – the Red Admiral butterfly.  While this is a common occurrence every spring for these butterflies to migrate north from their overwintering grounds in the southern US, the sheer numbers this year are staggering.  There are quite literally thousands of admirals in our back yards.

So what’s different this year?

There is much speculation about the warm spring weather (warmest March on record for many places) and often lots of misinformation to go along with some armchair entomology.  Most of the news sources I’ve come across say the warm spring has allowed these butterflies to flourish and reproduce in abnormal numbers.  That isn’t quite possible however, V. atalanta overwinters as an adult.  The southern states provide temps just warm enough for adult Vanessa butterflies to hide in the fall and be the very first to awaken in the spring to get a jump start on mating.  Even if the butterflies were awake in February the host plants were not yet up (thistles); the butterflies in our backyards are from last year.

But what if weather did play a role in this boom cycle?  Last year was a La Niña year with our beautiful and mild winter.  The year before was an El Niño, most of the eastern US was assaulted with winter and we suffered at the hands of the epic Chicago “snowpocalypse”.  Perhaps this combination depressed population numbers sufficiently in 2010/2011 which then decreased parasitoid load, allowing for greater overall butterfly fecundity in the summer of 2011.  Those overwintering butterflies were then granted a warm winter that could have allowed for a lower winter mortality.  As the butterflies moved north this spring there were no frosty nights to cut into populations – just lots of hungry birds.  The result would be an abnormal influx of migrating butterflies.

But then again…

Despite butterflies being so popular and well studied there doesn’t seem to be a perfect grip on what conditions each of the Vanessa species prefer.  The variables of host plants, population range, weather and parasitoids all play important roles in abundance and distribution.  Did the weather cycles of the last few years variably effect one species over another?  Who wants that PhD project (from hell)?

One of the best posts I’ve read is by Doug Taron over on Gossamer Tapestry – he is skeptical of this warm weather theory.  Critically this irruption is effecting only the population of the Red Admiral and any theory involving weather would also likely effect other migrant butterflies like the Vanessa virginiensis – the American Lady.  He also points out that an abundant butterfly like the admiral has classic cyclical population booms and busts in sync with parasite populations.  I recall another summer in the late 90′s of staggering Admiral populations.  Parasites really do better explain what we see in our yards this spring.  While the weather might not have caused the abundance of V. atalanta, there can be no denying that butterflies of all species have woken up much earlier this year.

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