Not much news to report here in Klaipeda since last week, busy busy busy with work and finishing up reports! So as there isn't much to report on in the Erasmus World, I have some time to tell you more about the two lagoons in question...

Aside from them both sharing ‘lagoon’ status, they couldn’t be more different! It can be surprising how even small variations in environmental parameters can cause such remarkable differences in ecology and biology. However, when comparing the Baltic Sea to the Atlantic waters approaching the Strait of Gibraltar, it is easy to see how these two areas could be so different. Ok, so temperature is a major factor, of course. Each and every organism has strict limits to what temperatures they can cope with, in the same way that humans do. For example, in the Ria Formosa, the gilt-head bream (Sparus aurata) is a species native to these warm temperate/subtropical waters, also being widespread throughout the Mediterranean Sea. This species would never be found in the Curonian Lagoon simply due to the temperatures. Despite temperature being a major factor in an organisms range, it is also affected by a number of other factors, one of which is salinity. Salinity can be very low in rivers and lakes or anywhere close to a freshwater input, it can be high, like in the Red Sea, or it can be brackish, as seen in the Curonian Lagoon. Similarly to temperature, salinity can also limit the range of marine organisms. Currents and tides also have an impact on a species potential distribution, as well as other factors such as predators and competition with other species. The food web can be very complex or, occasionally like in areas of upwelling, very simple with few trophic levels; a species may have many predators or none at all!

Overall, the structure of the food webs of both of these areas follow a basic structure (see the diagram below, and yes - there are sharks in the Baltic Sea!) however, the species present at each of these trophic levels are entirely different, yet they manage to fulfil the same role.

and here's a video some might enjoy..

http://www.youtube.com/watch?v=OvKQhAuIZE4

The gilt-head bream (Sparus aurata), a species native to the Ria Formosa:

The pike-perch (Sander lucioperca), a species of fish found in the Curonian Lagoon: