Midges (Chironomidae)
Tuesday 11th October
See written piece about midges by pupil Steven MacMahon here.
As we were creating a laser level for our contours mapping one of the children noticed that in the mud beneath us, were lots of small red 'worms'. By walking in the mud of the dried-up-wetland, we accidentally churned up lots of them. It was easy to see from their bright red colour that they were not earthworms. We first thought they were just another type of worm.
See written piece about midges by pupil Steven MacMahon here.
As we were creating a laser level for our contours mapping one of the children noticed that in the mud beneath us, were lots of small red 'worms'. By walking in the mud of the dried-up-wetland, we accidentally churned up lots of them. It was easy to see from their bright red colour that they were not earthworms. We first thought they were just another type of worm.
On returning to class we showed it to Mr. Long who tweeted the above photo with an open question if anyone knew what they might be. We soon got a reply.
Turns out they are the larvae of non-biting midges. More info by clicking here. It makes sense that we would find them in the mud of the wetland. When the wetland is submerged on a calm evening they tend to swarm over the water. We noticed also that our swallows enjoyed swooping on them daily prior to their departure for sunnier climes. It was interesting for the children to see another animal that has a life-cycle in stages (egg to larva to pupa to adult). The most commonly known animal to school children is typically either the butterfly or the frog. |
Cameo appearance by the ground beetle!
Earthworms (Lumbricus terrestris)
Monday 3rd October 2016
(Read written piece by pupil Ciara de Klein by clicking here)
Today we took advantage of the dry weather and undertook one of our planned investigations of the wetland – a worm count. We wanted to see if the seasonally submerged wetland area had an effect on the worm population there so we decided to dig for worms in three different areas to compare results.
(Read written piece by pupil Ciara de Klein by clicking here)
Today we took advantage of the dry weather and undertook one of our planned investigations of the wetland – a worm count. We wanted to see if the seasonally submerged wetland area had an effect on the worm population there so we decided to dig for worms in three different areas to compare results.
- Outside the wetland.
- In the wetland area half-way between the edge and the centre.
- In the wetland centre.
After learning all about the earthworm in class, the class predicted that we would find lots of earthworms in A, less in B and less or none in C. This was based on the newly acquired knowledge that earthworms breathe through their skin and so would not stay in an area that was frequently waterlogged. However I proposed to them that maybe the worms would have returned in the drier months as the water table descended and the submerged area shrank. We would have to wait and see… |
Off with our shovels and containers to the wetland.
The difference in soil quality was clear to see. This was mainly down to the water content. We dug down below the water table to the subsoil in Location C next to the wetland centre to see if the hole would fill up. (Which it duly did by the next day.)
We also took soil samples from each of the three locations for soil testing in a few days’ time. The children took the three containers back to the class to begin the process of sifting through the soil for earthworms. |
Results:
The class’ prediction that A would have lots of earthworms, that B would have less and C none came true to some extent, the only difference being that B also had none.
My proposal that the worms would possibly have returned to previously submerged wetland area was unfounded.
On the evidence gathered from this investigation we can conclude:
- The wetland has changed soil conditions in the area making it too wet for the earthworms to live there.
- No earthworms will mean poorer soil quality in terms of nutrients and aeration (To be confirmed by results of soil test.).
- Poorer soil must have a knock-on effect on other plant and animal species in the area, including those that prey on earthworms.
Questions raised:
- Why do the earthworms not return to the wetland area as it dries out during the Summer?
http://www.earthwormsoc.org.uk/earthworm-information/earthworm-information-page-2