Race to metamorphosis

For a tadpole living in a transient pond created by rainfall, the key to its survival may be how fast it can develop into a land-roaming toad before the pond disappears. A study found that tadpoles of the Eastern spadefoot toad (Pelobates syriacus) will speed up their development if they sense the water level around them decreasing.

A lot of Eastern spadefoot toad species live in permanent ponds, so their habitat is stable and provides them adequate time to mature. However, along the Black Sea coast in Dobrudja, Romania, the varied rainfall patterns create ponds that can quickly form and disappear Continue reading

February 16, 2014Permalink Leave a comment

Back to Salt Marshes

Link to wikipedia for photo of salt marsh
Salt marsh. Photo from wikipedia, the free encyclopedia.

In a recent chat at work, my boss recalled his childhood days of hiking in the forest and adjacent marshes. Over a few years, he saw his backyard marsh dwindle as people cleared the land for urban development. The water drained from the marshes was enough to create a pool of water that froze into a natural ice hockey rink. The remainder of the drained marshes were then re-filled to redevelop the seemingly ideal, open and flat land.

Over the last few centuries, lots of salt marshes were lost to urban development. In Canada’s Pacific, 70% of salt marshes were destroyed by pollution or turned into agricultural land, roads, and residential areas, according to Capital Regional District. If you have ever been to Victoria, imagine that there used to be a marsh in the vicinity of the Empress hotel, or near Point Hope Shipyards.

Why does that matter? The article “Salt marshes are great Carbon sinks” covers Continue reading

November 12, 2013Permalink Leave a comment

Tracing the Adelie penguins’ food – are the Adelies in decline?

Imagine that you went out to buy shrimp but the closest grocery store didn’t have it in stock. Even then, the same store most likely has their selection of other seafood and meat for you to choose from, so that won’t be too devastating.

Adelie penguins can do the same: when they can’t get enough krill – a tiny shrimp-like crustacean that is their main source of food – they can switch to eating fish such as the Antarctic silverfish.

Link to flickr photo of Adelie penguin
Adelie penguin by Marie and Alistair Knock. Photo from flickr.

Such a switch can be triggered by a competitor for the Adelies’ food: baleen whales. When these whales arrived to the Antarctic in the spring to feed, they ate about 2000 times more krill than penguins would. Continue reading

October 21, 2013Permalink Leave a comment