This year the pond team put on another interactive show as part of Meet Mother Nature exhibit for Reading Science Week 2012. Those keen enough to get grubby and pond dip were able to see the early forms of pond life that are colonising the University campus ponds already this year.
Here is a snap shot of the work done in the first week of November to create our first set of wildlife ponds.
*fish not included
New ponds are going to be created along an Urban to Rural gradient across Reading. The work is scheduled to take place over the next few weeks and will see the creation of 15 new ponds. These ponds will be located in volunteer private gardens and will be left to colonise naturally, hopefully giving us an indication of the colonisation potential across different areas of Reading.
Thanks goes to our volunteers, for offering their gardens to be part of this research and to Pond Keeper, who have supplied the pond liner and underlay.
Our four Undergraduate Zoologists Alex, Verity, Chelsea and Evan. Are currently working on our Latin square expriment, which is looking at variables that affect pond colonisation. For more info visit Our Research page.
This is our other sampling method being used by Chelsea & Evan. Credit goes to Evan for making these simple yet effective samplers from recycled materials at zero cost.
Here is one of the two methods being used to collect the samples at each site. Verity & Alex are currently using this technique, which involves drawing three figures of eight in the lower, mid and upper regions of the pond. The net used is a fine mesh, rectangular aquarium net.
One type of freshwater invertebrate that we have identified from our ponds belongs to the family Culicidae, and is commonly known as mosquito larvae. We have found this species to be quite abundant in certain ponds. These larvae have a well-developed head with mouth brushes used for feeding. They also have a large thorax with no legs and a segmented abdomen.
They tend to be found on the surface of the water, and will only dive below the surface when disturbed. The larvae must come to the surface regularly, as located on their eighth abdominal segment are spiricles which they use to breathe through.
The larvae move in a figure of eight motion, and are often referred to as ‘wrigglers’. They move through propulsion with their mouth brushes.
Photo by Neil Phillips
The mosquito larvae mainly feed on algae, bacteria and other micro-organisms found towards the surface of a pond.
In order to grow, during their larvae stage, they shed their skin around four times, getting bigger each time. How long the larvae stay in the water depends on the temperature of the water, but generally takes between 7-14 days.
Water mites (Family: Hydracarina) are mainly found in fresh water habitats. They are usually brightly coloured and are normally between 0.5mm and 2mm in size. A water-mite cannot chew his food. When he attacks an insect larva or some other animal, the mite sucks the juices out of its body, much as a spider sucks the body fluids out of a fly.
Water mites look very similar to spiders in that they have four pairs of legs and they also have a pair of palps. What makes them different is that their bodies are fussed into one, however in spiders their bodies are divided into two segments (cephalothorax and abdomen).
One type of insect that has been observed in the ponds is the swimming mayfly nymph, Baetidae. There are 4 main types of mayfly nymphs: swimmers, burrowers, crawlers and clingers. This website shows the differences between them, and how to find out their genus: http://www.delawareriverguide.net/insects/nymphid.html. Swimming mayfly nymphs are mainly found in ponds and other still bodies of water. These pond invertebrates can be distinguished by their long, flat, torpedo shaped body which ranges from around 3-20mm in length. They have 3 thin long tails at the end of their abdomen, and 6 legs with claws on the end joined onto the side of their thorax. Mayfly nymphs have gills on the sides of their abdomen, which can be feathery or plate-like in structure, which take in this oxygen from the water. They are used in water quality assessments, as they tend to live in areas of high oxygen levels and so are a good indicator of how clean the water is. (Species shown below is an olive swimming mayfly nymph caught in the river Teifi in Wales)
These species are herbivores as they eat plants and algae in the water, and are preyed upon by many different types of species, such as water spiders. They live nearly all their life as a nymph, which can be from a few months to a year, until they shed their skin and emerge as an adult to live out of the water. This process normally occurs in May, hence the name of mayfly. They only live in their adult form for a day or so, of which they use to find a mate and reproduce before they die.
This video, from Ralph and Lisa Cutters “Bugs of the Underworld”, shows more detail on the life cycle of mayflies in general:
