In the Small, Small, Pond

Mosquito Larva
Mosquito larva hanging out in the water column.

We’ve had a couple of days of rain and several centimetres of water has been sitting in a small Rubbermaid tote that we use when gardening. I happened to look into it earlier this week when getting ready to put the yard waste out for Courtenay’s recycling program to pick up and noticed that things were happening in this small, small pond.

Small, Small Pond
A small Rubbermaid© tote makes a perfect home for mosquito larva.

I’ve always loved pond dipping and have worked with a number of NGOs doing pond programs so I knew exactly what was happening in the tote. Mosquitoes had laid eggs in the water and those had hatched. Mosquitoes have a four stage life cycle that begins with an egg (I guess you could also apply the old which came first argument here – the mosquito or the egg?). In 24 hours it hatches into a larva (also known as a wriggler). The larvae must survive for 7 to 14 days, eating algae and small organisms in the water. After that time it changes into a pupa (also called a tumbler). It stays in this part of the life cycle for 1 to 4 days before emerging as an adult mosquito.

Mosquito Larva
A pair of mosquito larvae – note the bristles and head downward position. A small snorkel is located a the rear of each wriggler.

At this point, all of the mosquitoes appear to still be in the wriggler stage. They were foraging on the algae that was growing on the sides and bottom of the tote, wriggling up to the surface and floating head down with their breathing tube (located at the rear of the larva) just breaking the surface of the water.

Mosquito Larva
A side profile of a mosquito larva showing the “snorkel.”

They were aware of me observing them and moved quickly to the bottom and side of the tub in order to escape if I shifted my position. I also noted a few midge larva as well, long and thin and transparent with just a hint of red. These might be Cricotopus sp. given their body structure.

Midge Larva (Cricotopus sp.)
A few transparent midge larva (Cricotopus sp.) also were found in the tote.

So I now have a dilemma. Standing water obviously provides a place for mosquitoes to lay eggs which will grow into adults. Although I should probably dump the water out I think that I’m going to leave it for a while and watch as these insects cycle through the stages of their lives. The opportunity to observe this process is worth a few mosquito bites! What do you think – should they stay or should they go?

Read more about what folks think about mosquitoes at Neighborhood NatureButterfly’s Psyche, and The Natural Capital.

If you’ve enjoyed this post, you might also like to check out Macro Monday for more photographs of the world of the small.

Macro Monday