Download Rat-tailed Maggot

Invertebrates
Rat-tailed Maggot
The rat-tailed maggot is the immature or larval stage of a fly that resembles a
honey bee. These 3/4 inch long whitish larvae are different from other fly
maggots in having a 1/2 inch long "tail" that is used as a breathing tube when
they are in the water.
Large numbers can be present in most any accumulation of stagnant water,
such as manure pits or lagoons, where they feed on decaying organic matter.
The maggots become a nuisance when they crawl away from their breeding
site to find a dry place where they can transform to the adult stage.
Tubifex
This aquatic angleworm is right at home in mucky water. Sometimes called a
sludge worm, it can even live in highly polluted waters. It buries its head in
the bottom mud to eat while letting its tail wave in the current. Just like a
land worm, an aquatic worm eats mostly dead plants. If a particularly juicy
dead animal is nearby it will munch on that too, just as long as it doesn't have
to travel too far. This worm breathes through its skin and can live where
there is hardly any oxygen.
Mayfly Larva
While there are many species of mayfly, all are characterised by three long
tails, a long larval stage and the distinctive, vertically held wings of the resting
adult. Mayflies are sensitive to pollution and as water quality decreases so too
does the diversity of mayflies present.
Molluscs
Freshwater mussels occur in the sediments of many permanent streams, river
and lakes. They are 'filter-feeders', sucking water from around them in with
one extensible siphon, filtering out small particle, algae and bacteria for food,
and then exhaling filtered water through another siphon. They are not
tolerant of polluted water, especially water containing toxins which poison
them as they filter feed.
Alderfly
Alderfly larvae look like caterpillars and can be red-brownish in colour. They
have external gills along both sides of the top of their abdomen, three pairs of
legs on the middle section of their body and a straight, single feathery tail.
Each leg has tiny pincers at the end. They prefer to live in the mud or under
stones and are sensitive to pollution but can live in somewhat polluted water.
Stone fly
Stoneflies are insects often found resting on stones. Stonefly nymphs have
two long tails- these are the sense organs but also help the insect to move.
Each leg has two claws that are used to cling to rocks or sticks. Their bodies
are streamlined so they don't get swept away by the water current. They are
sensitive to pollution.
Caddis fly
They live in a wide range of environments from fast flowing streams to
freshwater ponds. Their soft bodies are usually covered in a protective silky
case. They use the hooks at the end of their abdomen to hold on to their
cases. Some species do not live in cases, using their hooks instead to cling to
the stream bed and also to drag themselves backwards to escape from
predators. Very sensitive to polluted water- only lives in very clean water.
Leech
Leeches are segmented, cylindrical worms with a sucker on each end, one
being a mouth. In many forms, the mouth has three small jaws equipped with
sharp teeth. Leeches can swim. They can also walk, which they do in a
looping manner. Leeches are found in warm, slow moving rivers or ponds.
They prefer shallow water, and live under rocks and debris, or on plants,
where they attach themselves to something solid. Leeches are able to survive
where there is not much oxygen. They can also tolerate various chemical
pollutants.