Hello everyone and welcome to food chains week!
All our resources for adaptations, which we covered last week, can be found here
Sorry that today's post is a little late but I was over on Burhou with Filip, our Ramsar officer, doing the first of this year's puffin productivity counts. This involves sitting quietly for a couple of hours and watching the puffin burrows. This can help us determine how many burrows are being used as nests and how many chicks we might get. Where I was I spotted 7 puffins coming and going from their burrows! However until the chicks hatch it is difficult to really tell how many puffins are nesting because this is when they really start coming back and forth with food - we expect this will be in the next week or two so keep checking the cameras. If any of you were watching at lunch you might have seen us pop up for a minute or two as we checked the position of the cameras and gave the lenses a bit of a clean!
Food chains show how plant and animal species rely on each other for food. A simple food chain shows the transfer of energy and what species is eaten by what other species. For example the most common food chain for our puffins is:
Plankton ------>Sand Eels ------> Puffins
While we were over on Burhou we spotted lots of evidence of the food chains that happen on the islet. For example we found lots of shellfish (especially crab) remains - can you think of two bird species that might eat them? And why would we find remains on the rocks where they eat them?
As we were leaving we also saw two of the seals that live and breed near Burhou, they would be the top predator of their food chain because they have nothing that predates them (on Alderney anyway!). The producer in the seal's food chain is plankton or seaweed as they are the bottom of the food chain - a food chain always starts with the plant producer.
In most habitats the interaction between species is usually more complicated than a food chain, which is why we have food webs. This shows all the different interactions between species from the producers to predators. Most species are adapted to have a preferred food (like puffins with sand eels) but many will also eat other things. Can you make a food web (or chain) for yourself based on some of the things you ate today?