30 October 2009

2 more data points (or is it datum points?)


Very little research has been published on the life cycle, ecology, behavior and the general biology of the native slugs (family Philomycidae) of northeastern North America. Megan Paustian and I started doing some work on the water loss and regain characteristics of one species, Megapallifera mutabilis, early in the spring of this year (see this post).

At about the same time, I decided to understand their annual generation cycle better, especially to figure out if adults survive the winter. It's a simple project, really. For 2 years, I will measure the body dimensions and/or weights of live slugs throughout the year. That's about it. The collective data will show how the members of the population change during the year. The important thing is to take as many measurements as possible on relatively warm days in December and also towards the end of March as soon as the weather starts to warm up. If there are large slugs in December and in March that will mean that the adults survive the winter.

The photograph shows 2 of the slugs getting weighed in the field about a week ago. They were adults and quite heavy, as far as this species goes.


pascal said...

Your winter-slug studies sound interesting. I would be quite interested to know how gastropods deal with the cold.

Megan said...

Yes, >4 g is impressively heavy for Megapallifera! I don't think I've weighed any Philomycids that size, at most maybe 3.8 g for a P. carolinianus.

To ruin the punchline, I'm pretty sure that Megapallifera do overwinter. The largest ones I've ever seen were out in the spring. It's not clear to me whether these individuals were 1 or 2 years old, though.

I would like to add some data points to your study.

AnswerBank said...

Hi There. You might be interesting in Snag Hunting (if you are not already aware of it!)

I'll quote from a recommended source:

"Since the middle ages there has been a quaint ritual event occurring in the wildest fenland of East Anglia; Snag hunting. It goes unnoticed by the majority of the British Isles but is still kept alive by small groups of passionate young men in search of the secret honours of being the snag hunting champion."

(Source: http://www.theanswerbank.co.uk/ChatterBank/article/a-great-fen-tradition-under-threat-snag-hunting )

I hope you run something on this - especially considering the effects of Slugging on the sport!

All the best,


PS. Further information: Snag Hunting - The Inside Story: http://www.theanswerbank.co.uk/ChatterBank/article/snag-hunting-the-inside-story/

Anonymous said...

Hmm, the snag thing is an unfunny hoax article, which admits its untruth in a disclaimer at the bottom. It's rather lame, and not worth the effort required to go and read it. Someone needs to learn that writing a more or less coherent account of something that is untrue is not a sufficient method to create humor.

Susan J. Hewitt

AnswerBank said...

Not a problem Susan, it isn't for everyone!

Try these two instead:



In response to:
"Someone needs to learn that writing a more or less coherent account of something that is untrue is not a sufficient method to create humor."

You can't teach an old dog new tricks.

All the best,