Teac her Resourc e Pac kage

Department of Environment and Natural Resources South East Natural Resources Management Board

For more information please contact the Environmental Education Coordinator Department for Environment and Heritage

11 Helen St Mt Gambier SA 5290 Phone: 08 8735 1145

Fax: 08 8735 1135

Updated Jul 2010

Acknowledgements

The comprehension exercise was developed by Matthew Cattanach of the Onkaparinga Waterwatch Network. The life cycle graphics were adapted from the Waterwatch South Australia Manual.

The habitat zone pictures are adapted from the Waterwatch Australia Technical Manual.

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Contents

1. What are Macroinvertebrates?

Learn about the fea tures of mac roinverteb ra tes and the d ifferenc e between a macroinvertebrate and an invertebrate.

2. What do Macroinvertebrates eat?

What do mac roinverteb ra tes ea t? How do they ea t their food sourc e? Learn about the food web concept.

3. Life Cycle

Learn about the life c yc le of inverteb ra tes. Draw and label a d iagram of a typ ic a l macroinvertebrate life cycle.

4. Macroinvertebrate habitat

Learn about what places within a waterway macroinvertebrates like to live in. Find out why a healthy habitat is important for macroinvertebrates.

5. How do Macroinvertebrates breathe

Learn about some of the fasc ina ting ways tha t mac roinverteb ra tes a re ab le to b rea the under water.

6. Threats to aquatic invertebrates What is having a negative effect on the macroinvertebrate populations in the South East?

7. Macroinvertebrates found in the South East Learn about the common macroinvertebrate species found in the South East?

8. Additional resources

I have inc luded a list of g rea t resourc es to help your c lass lea rn more about macroinvertebrates

9. Further Learning Opportunities

Some suggested activities for your class to complete.

10. Macroinvertebrate Fact Sheets

Macro Facts - Some b iza rre and interesting fac ts about some of the more c ommon macroinvertebrate species found in the South East and throughout Australia. Macroinvertebrate Habitats- Information on the d ifferent hab ita t zones inhab ited by aquatic macroinvertebrates.

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A Damselfly Larvae has a skeleton on the outside of

its body called an exoskeleton to protect

itself.

A Dragonfly Larvae

1. What are Macroinvertebrates? Mac roinverteb ra tes a re aqua tic anima ls tha t a re quite sma ll but c an be seen with the naked eye (Gooderham & Tsyrlin, 2002). The word mac ro means b ig and the Greek word inverteb ra te means no bac kbone and this is reflec ted with mac roinverteb ra tes being visible to the naked eye and containing no backbone.

They a re a d iverse group of anima ls tha t c an be worms, c rustac eans or insec ts inc lud ing beetles, bugs and even sp iders. Mac roinverteb ra tes c an be found in both running wa ter and in still water.

Mac roinverteb ra tes have spec ia lised body systems tha t a llow them to live in wa ter. They have g ills instead of lungs, a llowing them to ob ta in oxygen from the wa ter. Different species also have different mouthparts depending on what they eat.

One of the most c ommon questions asked is Do mac roinverteb ra tes grow?

Well, the answer is, yes of course they do. All invertebra tes grow. Some spec ies suc h as leec hes and sna ils have skins

tha t c an grow a t the same ra te as the rest of the anima l and simp ly get b igger the same way as we do. Both c rustac eans and insec ts have exo-skeletons, whic h don t grow onc e they have hardened .

These anima ls a re c a lled a rthropods and shed their exo-skeleton as they grow to avoid been c ompressed inside this outer shell. They do this by rep lac ing the old shell with a new one which is bigger.

No Bones, No Worries!

Aquatic Mac roinverteb ra tes don t have a bac kbone and this means tha t they a re highly prone to becoming damaged in the water.

Aqua tic mac roinverteb ra tes have developed some amazing fea tures over time to help p rotec t them from damage in an aqua tic environment. These fea tures inc lude c onta ining a p rotec tive outer shell a round their body to p rotec t their organs as seen on a d ragonfly and damselfly la rvae and most c rustac eans. Other types of mac roinverteb ra tes will live in ha rd ob jec ts tha t a re found in wa terways suc h as inside stic ks and twigs. The c add isfly la rvae is one examp le. This anima l will ea t through the c enter of a stic k and c a rry the stic k around with it while in the water.

The Caddisfly Larvae uses objects in the water such as

sticks to protect itself.

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2. What do macroinvertebrates eat? The food web is a c onc ep t, whic h exp la ins how d ifferent organisms ob ta in food within an ec osystem. The food web c onsists of various levels inc lud ing p roduc ers, herb ivores, detritivores and p reda tors. At the bottom of the food web a re the p roduc ers; these a re organisms suc h as p lants and a lgae. These organisms c rea te their food in the form of energy from sunlight or raw materia ls. Herb ivores a re the sec ond level and they ea t p roduc ers. Herb ivores c an be either sc rapers or shredders; with sc rapers sc rap ing sma ll layers of a lgae off surfac es and shredders whic h c hew through leaves and p lants. Detritivores ea t a mixture of lea f litter, woody debris and dead organisms. Many detritovores are also herbivores because their mouthparts and digestive systems are similar. The p reda tors a re a t the highest level and feed off la rger inverteb ra tes they c an feed on either producers or herbivores.

Mac roinverteb ra tes a re c lassed as herb ivores, detritovores or p reda tors. This means tha t some spec ies inc lud ing sna ils ea t p roduc er organisms suc h as p lants and a lgae, while some ea t dead p lant materia l or detritus. Many spec ies suc h as a Dragonfly La rvae feed off other smaller animals, including smaller invertebrates making them predators.

Mac roinverteb ra tes c onta in spec ia lised mouthparts, whic h determine wha t type of herb ivore they a re. Herb ivores c an be either sc rapers or shredders with sc rapers c onta ining b rush or b lade like mouthparts equipped for removing firmly a ttac hed a lgae. Alterna tively, Shredders contain chewing mouthparts.

Some Mac roinvertab ra tes a re p reda tors or c a rnivores, this means they p rey on other smaller animals and eat meat. These animals tend to contain piercing mouthparts.

Mouthparts of Dragonflies and Damselflies. These have been adapted for capturing prey.

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What Eats Macroinvertebrates?

Picture from: Environmental Starters Gould League VIC.

Many animals eat macroinvertebrates. In the picture above the invertebrates have been highlighted. The vertebrate predators of macroinvertebrates include; frogs, fish, birds and mammals like water rats.

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3. Life Cycles The life c yc le of a mac roinverteb ra te is quite simp le. They ha tc h from eggs and spend a long time develop ing into a la rvae or nymph stage. Onc e the la rvae or nymph has grown they become adults and can reproduce to begin the cycle again.

The following is a diagram of a macroinvertebrate life cycle. You could use this diagram for your students to draw and label the cycle or build a model using clay or recycled materials such as icy pole sticks and pipe cleaners.

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3. Habitat The qua lity of hab ita t is important for a ll mac roinverteb ra tes surviva l. Mac roinverteb ra tes live in a range of hab ita ts rang ing from flowing c reeks and streams to still ponds and lakes, wetlands and estua ries. In any of these wa terways aqua tic vegeta tion, lea f litter and woody debris all provide the essential habitat for a range of macroinvertebrates.

Streams, Creeks and Rivers Flowing wa terways suc h as c reeks, rivers and streams a re often b roken into 2 sec tions; fast flowing and slow flowing. The fast flowing a reas a re known as riffles . Mac roinverteb ra tes found in the riffle a reas live on and under roc ks so they c an hold onto the streambed and not be washed down stream.

The slow flowing a reas a re known as pools . Mac roinverteb ra te spec ies found living in this area are free living and are often found swimming around in the water.

A typical river habitat.

Ponds and Lakes Lakes offer a d iverse range of dep ths whic h supports a range of aqua tic flora and this p rovides a va riety of hab ita t for mac roinverteb ra tes to inhab it. There tends to be a d iverse range of spec ies living in lakes bec ause of the range of hab ita t tha t is p resent within the water body.

Ponds and dams whic h a re not d irec tly c onnec ted to flowing streams have a low d iversity of mac roinverteb ra tes. This environment c an sometimes not a lways c onta in wa ter and therefore c an spend ha lf of the year d ry. Spec ies tha t fly suc h as flies mosquitoes and midges tend to colinate these areas because the waterbody is not connected to a flowing waterway.

A typical pond habitat

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Wetlands and Marshes Wetlands provide some of the most diverse habitats and often consist of a large diversity of spec ies. These sites a lso spend some part of the year d ry. Wetlands support a high d iversity bec ause they tend to c onta in a high nutrient c ontent making them extremely p roduc tive environments for the development of aquatic flora.

A typical wetland habitat

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The Backswimmer collects a bubble of air from the atmosphere and stores it on it s belly!

4. Breathing There a re 2 ma in sourc es for ob ta ining oxygen for aqua tic macroinverteb ra tes; the a tmosphere just above the wa ter surfac e and the oxygen d issolved in the wa ter. The oxygen p resent within the wa ter is c omb ined with hydrogen and is therefore not ava ilab le itself, as it c annot be separa ted from the hydrogen, it is therefore ava ilab le as d issolved oxygen.

Oxygen from the atmosphere Animals that obtain oxygen from the atmosphere either swim to the surface, break through the surfac e wa ter to ob ta in their oxygen supp ly and hold onto their oxygen supp ly in the wa ter. Alterna tively, they may ob ta in a long tube whic h the anima l c an poke up to the surface, like a snorkel to obtain their oxygen supply.

Anima ls tha t c a tc h oxygen from the a tmosphere must be ab le to store this oxygen somewhere while they a re swimming under the wa ter. Some anima ls suc h as the Bac kswimmer c a rry an a ir bubb le with them under their abdomen and use a row of ha irs a long the edges to trap the oxygen, while other anima ls inc lud ing many beetles store their oxygen under their wing pads.

Anima ls, suc h as a mosquito la rvae c onta in a short tube a t the end of its body whic h c an be extended into the a tmosphere where they sp read a row of ha irs a long the

water surface, leaving an opening for the animal to take in oxygen.

Using Dissolved Oxygen Another method for ob ta ining oxygen for anima ls living in wa ter is to use the d issolved oxygen p resent in the wa ter and develop ing g ills. Aqua tic inverteb ra tes tha t have developed g ills b rea the by passing a water c urrent through their body and out through their g ills. The g ills c onta in b lood vessels and as the wa ter passes through them, oxygen passes into the b lood stream and c a rbon d ioxide passes out into the wa ter. A Dragonfly Larvae contains gills inside its rectum and breathes by taking water into its rectum and then forcing it out again.

A Mayfly Larvae which has its gills at their sides of their body.

Gills on a Damselfly Larvae

Mayfly Larvae gills

Damselfly Larvae showing their gills at the base of their tail which enable the

animal to breathe under water.

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5. Threats to macroinvertebrate populations Dec lining wa ter qua lity, b lue green a lga l b looms, c ontamina tion from pestic ides, nutrient and sed iment pollution, mic robes and sa linity a re just some of the issues a ffec ting many wa terways in Austra lia . All of these issues a ffec t the qua lity of our wa ter and pose a threa t to our d rinking wa ter supp lies, but wha t a ffec t does this have on mac roinverteb ra te populations that call our rivers and streams home?

There a re a number of ma jor loc a l issues a ffec ting mac roinverteb ra tes in the South East inc lud ing dec lining wa ter qua lity, na tive vegeta tion c lea ranc e and semi permanent wa ter bodies or waterways that only have water for short periods of the year.

Let s take a look a t how eac h of these ma jor issues a ffec ts mac roinverteb ra tes and wha t can be done to manage these issues.

Water quality

Dec lining wa ter qua lity has huge imp lic a tions for mac roinverteb ra te popula tions. Water qua lity c an dec line due to a number of possib le reasons; a c hemic a l sp ill or dump ing , an influx of nutrients suc h as phospha te and nitra te, rising sa linity and inc reased turb id ity from erosion or stoc k c rossing the wa terway. Many types of inverteb ra tes a re sensitive to water pollution whic h means any pollution tha t enters a wa terway has d ramatic effec ts on ind ividua ls and potentia lly their entire popula tion. Should pollution enter a wa terway mac roinverteb ra te numbers will dec line and eventua lly none will c olonise tha t pa rtic ula r area.

Native vegetation clearance

Hab ita t fragmenta tion or the c lea ring of na tive vegeta tion is a c onc ern for mac roinverteb ra te popula tions. The c lea ring of na tive vegeta tion ultimately reduc es the hab ita t ava ilab le for mac roinverteb ra te popula tions to c olonise. By reduc ing their hab ita t mac roinverteb ra tes a re more susc ep tib le to p reda tion from la rger anima ls, have a reduc ed food sourc e and wa ter qua lity in the system they live in will dec line due to less filtering of nutrients and higher soil erosion ra tes whic h c ould lead to a popula tion rise in exotic plants and animals.

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6. Macroinvertebrates found in the South East

The South East reg ion is a b iolog ic a lly d iverse a rea for aqua tic mac roinverteb ra tes and more than 350 types of macroinvertebrates have been recorded in the region since 1994.

The high d iversity of spec ies is most p robab ly due to the high ra infa ll evident in the reg ion whic h c rea tes an abundanc e of hab ita ts rang ing from flowing c oasta l streams to seasona l waterways. This varying number of habitats allows a variety of species to populate an area.

The most c ommon mac roinverteb ra te spec ies found in the reg ion inc lude roundworms, sna ils, amphipod c rustac eans, midge la rvae, mayfly la rvae and freshwater shrimps. Along with these c ommon types there a re a lso severa l ra re types inc lud ing stonefly nymphs, native snails, beetles and freshwater crayfish.

Mac roinverteb ra tes have some interesting and fasc ina ting fea tures tha t have a llowed them to live in an aqua tic environment. Here is some information about some of the common types found in the South East which may help you find and identify them.

Roundworms Eats: Eat organic matter both living and dead. Identification clue: The end of roundworms taper to a point. Lives: Roundworms prefer to live amongst the strata where they burrow in.

Snails Eats: Sna ils a re sc raper feeders whic h sc rape a lgae from roc ks and plants. Lives: Lives amongst the weeds and stones in a slow flowing waterway.

Amphipod crustaceans Eats: Dead and decomposing plant and animal matter Lives: These anima ls c an live in a va riety of environments from flowing water to stagnant pools.

Midge Larvae Eats: Algae and debris and can be predacious, feeding on other animals. Identification clue: Worm like animals with some types been red in body colour. Lives: Lives in the sediment at the bottom of the waterway.

Caddisfly Larvae Eats: Are sc raper feeders whic h sc rape a lgae from the roc ks they live on, or filter ma teria l from the wa ter c urrent. Some types a re even predators of insects and crustaceans. Identification clue: Makes a portab le c ase from stones, p lant materia l and sed iment and c a rries this around with it like a tortoise shell. Lives: At the bottom of the wa terway amongst the sediment and rocks.

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Mayfly Larvae Eats: Scraper feeders whic h sc rape a lgae from roc ks or ea t dec aying p lant and animal material. Identification clue: Have fea thery g ills on their abdomen and 3 ta ils a t the end of their abdomen. Lives: Under rocks and logs in both flowing and non flowing streams.

Freshwater Shrimp Eats: Plant and animal material Lives: Low flowing rivers and still waterways.

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7. Macroinvertebrate Materials

Books

Child, J. (1968). Australian Pond and Stream Life. Lee Fung Printing Company, Hong Kong.

Gooderham, J., Tsyrlin, E. (2002). The Waterbug Book. CSIRO Publishing, Victoria.

Hawking , J., Smith, F. (1997). Color Guide to Inverteb ra tes of Austra lian Inland Waters. Cooperative Research Center for Freshwater Ecology, Albury.

Hodson, A. (2002). Minibeasts of Wetlands. Urrb rae Printing Servic es, Netherby, South Australia.

Miller, R. (1996). Freshwater Invertebrates. Gould League of Victoria, Australia.

Wallis, W. & Smyth, C. (1992). Pond ing. Ac tivities for your loc a l lake, pond or pudd le. Gould League of Victoria, Australia.

Websites

Critter Catalogue. www.sa.waterwatch.org.au/programs.htm#new

Waterwatch Australia Technical Manual. Biological Parameters. www.waterwatch.org.au/library/module3/index.html

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Further Learning Opportunities

Marvelous Macro Minds!

How muc h do you know about mac roinverteb ra tes? Undertake a short c lassroom quiz to find out who is the master mac ro

in your c lass. Refer to the information c onta ined in this

pack for some ideas for questions and the answers. Some questions might include:

If I contained gills for breathing what method would I use to obtain oxygen?

The Greek word invertebrate means?

What order does a macroinvertebrate life cycle take?

Where do Macro s live?

Using the hab ita t c ross sec tion poster and wa terbug p ic tures (loc a ted a t the end of this pac kage) c olour in the hab ita t poster and the wa terbugs and stic k the wa terbugs onto the poster in the habitat zones preferred by different macroinvertebrates.

My Favorite Macro

Prepare a report on your favorite aqua tic mac roinverteb ra te spec ies. The report c ould contain information including:

The common and scientific name of the macro.

What type of habitat it lives in.

What does it eat and the type of feeder it is classified as.

Some interesting features about the animal.

Draw a picture of the macro

The Waterbug Hunt

Comprehension Exercise Read the c omprehension exerc ise, Wa terbug Hunt p repared by the Onkaparinga Waterwatch Network and complete the comprehension questions at the end.

Macro Sampling

Practical Activity Take a visit to your loc a l wa terway and c ollec t and identify some aqua tic mac roinverteb ra tes. Identify as many wa terbugs as possib le and determine the pollution index for this site. Contact Waterwatch coordinator 87 351145.

Create A Critter

Creative Activity Reconstruct your favorite water critter using a variety of features from common macroinvertebrates found at you local Waterwatch site.

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AQUATIC MACROINVERTEBRATE WORD FIND

Why are aquatic macroinvertebrates important in determining water health? Find a ll the mac roinvertebra te words in the puzzle and string together the remaining letters to answer the question.

BACKSWIMMER DRAGONFLY SPRINGTAIL WATERMITE CADDISFLY FISHINGSPIDER STONEFLY WATERSCORPION COPEPOD MOSQUITO THREADWORM WATERSTRIDER CRANEFLY PHANTOMMIDGE WATERBOATMAN WHIRLIGIGBEETLE DAMSELFLY SOLDIERFLY WATERFLEA

L

T

E

E

B

G

I

G

I

L

R

I

H

W

C A D D I S F L Y W E I A N I A E L F R E T A W D T R A I S M O S Q U I T O E Y E M C T H R E A D W O R M L D T A T E I W A T E S R Q F I A Y L F E N A R C U A L R R O I T D R A G O N F L Y E T B Y A N D L R S E V E L I S R D O P E P O C P O F P D R E S P R I N G T A I L O L E T S T O N E F L Y L D L O T A U N W A T E R M I T E S A W R E M M I W S K C A B R W T

E

F N P H A N T O M M I D G E

Y L F L E S M A D I O N O O

BACKSWIMMER

COPEPOD

DAMSELFLY

STONEFLY

WATERMITE

WATERSCORPION

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Comprehension Exercise The Great Waterbug Hunt Prepared by Matt Cattanach - Education Officer, Onkaparinga Waterwatch

Melissa and Robert

Melissa likes anima ls. So does her younger b rother Robert. At sc hool Melissa lea rned about

these amazing bugs tha t live in the loc a l c reek c a lled aqua tic mac roinverteb ra tes. On her

way home from sc hool she exp la ined to Robert, Aqua tic means wa ter, mac ro means you

c an see it with your eyes and inverteb ra te means an anima l without a bac k bone. So

Aquatic macroinvertebra tes a re wa terbugs tha t you c an see.

Can I see them? asked Robert.

Of c ourse , she rep lied .

Tha t weekend she dec ided to take Robert to a c reek near their house to see wha t kinds of

water bugs they could find.

Getting Ready

You need old c lothes and gum boots yelled

Melissa to Robert from the shed.

Melissa was searc hing through old d raws to

find some small jars. Earlier that morning Melissa

and her mother had made two stoc king nets

using old wire coat hangers and stockings.

Tha t should be enough ja rs now , sa id Melissa

to herself as she wa lked bac k towards the house. She wa lked to the front verandah where

Robert was waiting for her with his gum boots on.

O.K Robert. We have two stoc king nets, two empty ic e-c ream c onta iners, some p lastic

spoons and five sma ll g lass ja rs. Oh, and I a lmost forgot about the identific a tion sheet.

Robert pointed to the identific a tion sheet and asked ,

What will we use tha t for?

We need it to work out the names of the wa terbugs we

find , rep lied Melissa .

Robert then asked , Should I get my new magnifying g lass

as well?

That s a grea t idea , answered Melissa .

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At the creek

Melissa and Robert a rrived a t the c reek to see a tortoise sitting in the sun on a log . Robert

pointed and yelled ; look a t tha t .

The startled tortoise scurried into the water and disappeared with a splash.

What d id you do tha t for? sighed Melissa . If we keep quiet we ll see heaps more

anima ls. Try to be quiet .

O.K agreed Robert wishing he had been ab le to see more of the tortoise.

Melissa and Robert quietly put their equipment on the ground and then c a rried their nets

to the water s edge.

You sc oop for wa terbugs in the reeds and I ll sc rape a long the bottom , sa id Melissa .

What did they find?

After swishing his net in the reeds for a while Robert

notic ed there was mud and dead leaves in his net. He

looked more c a refully into the net and saw little bugs

wriggling around.

I ve got some he c a lled out to Melissa .

Well put them in the ic e-c ream c onta iner , she

rep lied , and add some water so the bugs don t d ie .

O.K , rep lied Robert.

Soon a fter he was peering exc ited ly a t the bugs zooming a round in his ic e-cream

container.

Try to sc oop the bugs into a ja r , sa id Melissa .

Robert and Melissa both used their spoons to sc oop the bugs into ja rs. Then Robert used his

magnifying g lass to peer a t the bugs. Some looked like minia ture sna ils and others were

swimming around so fast it was hard to see them.

Melissa began to recognise some of the bugs and showed Robert what to do.

O.K, see how this one has six legs and a long thin body. And , see how it has three ta ils.

Well tha t means it s a Damselfly la rvae. See it on the identific a tion c hart?

Robert was nodd ing in agreement. Robert looked bac k in his c onta iner and shouted out in

excitement. I found a yabby! He c a refully p ic ked up the sma ll yabby with his fingers and

put it in a glass jar of its own.

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Why count the bugs?

Melissa held up the Identific a tion c hart and sa id , O.K So we ve found ; Damselfly La rvae,

Dragonfly La rvae, Yabb ies, Shrimp , Bac kswimmers, Freshwater Sna ils, Fla tworms, Mosquito

La rvae, Sc uds, Water mites and Water Sp iders.

Tha t s 11 d ifferent kinds of wa terbugs , rep lied Robert.

We found some bugs tha t a re pollution sensitive , she sa id .

What does tha t mean? Robert asked.

It means tha t if there is some pollution in the wa ter then they might d ie.

So there isn t muc h pollution in this wa ter?

There mustn t be .

The turtle again

After the exc itement of the wa terbug hunt Robert and Melissa were sitting under a tree

quietly looking a t the c reek. Robert had wanted to take his yabby home. But Melissa had

suggested they put a ll the bugs bac k where they belong . Robert still wasn t sure it was the

right thing to do. He thought the Yabby would make a wonderful pet. It c ould sit on his

bedside table in a jar, and he could feed it little pieces of meat.

Mum and dad have to wash the c a r on the grass from now on , sa id Melissa .

Why?

Bec ause if they wash it on the road the c hemic a ls in the detergent will end up washing

down the d ra ins and into this c reek. And tha t means the pollution sensitive wa terbugs will

d ie .

As Melissa pointed to the creek she noticed the water rippling near the log where they had

seen the tortoise. A head sta rted to poke out of the wa ter and then a shell. She whispered

to Robert, have a look a t tha t .

Hey it s the tortoise, and he s got my yabby! c ried Robert. With a quic k sp lash the tortoise

was gone.

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Comprehension Questions:

1) What equipment did Robert and Melissa use on their waterbug hunt?

2) What does the word aquatic mean?

3) Name two of the macroinvertebrates that Melissa and Robert caught.

4) What does pollution sensitive mean?

5) What c ould Melissa s parents do to help save pollution sensitive wa terbugs?

6) What do you think pollution tolerant means?

7) How many different types of bugs did they catch?

8) What did this tell them about their site?

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Fact Sheet 1

Mighty Macro Facts Aquatic Macroinvertebrates are large waterbugs that we can see with our naked eye that don t have a backbone. They include larval stages of various insects, worms, snails and crustaceans. Aquatic Macroinvertebrates are bioindicator animals, this means their presence may define the health of the environment they are living in. Many Aquatic Macroinvertebrates are sensitive to changes in water quality while some have the ability to tolerate changes in water quality.

Macro Facts

Here are some fun facts about our aquatic macroinverteberates that make them so fascinating for us to study.

A Leech has exactly 34 body segments

All arthropods (insects, spiders and crustaceans) shed their outer shell during their growth. A Yabbie can have 10 to 20 shells during its lifetime.

Midge Larvae contain the substance hemoglobin in them which gives them a red appearance.

If a Flatworm is cut in half it is possible that the 2 halves can develop into 2 new individuals!

The bright red colouring of a water mite is a defence mechanism against predators. The red colouring is a distasteful substance that the water mite secretes.

Copepods live for less than 2 months.

Dragonfly Larvae breathe using gills at the end of its abdomen, in other words it breathes from its bottom.

Macro Websites

Critter Catalogue. www.sa.waterwatch.org.au/programs.htm#new

Waterwatch Australia Technical Manual. Biological Parameters. www.waterwatch.org.au/library/module3/index.html

www.bugsurvey.nsw.gov.au

www.ento.csiro.au/Ecowatch

www.mdfrc.org/bugguide

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Fact Sheet 2

Macroinvertebrate Habitats

A habitat is described as the area where an animal can successfully feed, breed and survive, it is the home of an animal. Aquatic Macroinvertebrates live in a variety of habitats including riffles, edge and benthic. Let s find out where these habitats are in a waterway.

Riffle Zone

The riffle zone is the fast flowing a rea of a c reek or stream. They tend to be sha llow with the wa ter flowing over a substra te whic h inc ludes lots of roc ks, pebb les and gravel. These roc ks, pebb les, gravel and exposed snags help anima ls estab lish territories and assist in the anima ls naviga ting their way a round the wa ter. Common mac roinverteb ra tes found here include stonefly and mayfly nymphs and shrimps.

Pool Zone

Pools usua lly have sandy or muddy bottoms and a re genera lly less d iverse than the riffle zone. The hab ita t ava ilab le is less suitab le for mac roinverteb ra te popula tions and taxa found genera lly a ttac h themselves to aqua tic p lants, roots, logs and other submerged objects.

Edge Zone

The edge hab ita t is defined as an a rea where little or no c urrent exists. There is little or no vegeta tion and is often in quite deep wa ter. The edge may have overhang ing vegeta tion, underc ut banks, root mats or other suitab le hab ita t whic h p rovides c over and refuge for mac roinverteb ra tes. Dragonfly and damselfly la rvae, wa ter mites, wa ter boatman and backswimmers are commonly found in this habitat zone.

Run Zone

Runs are generally deeper and contain slow moving wa ter. Sma ll pa rtic les tend to settle on the bottom of the wa terway and this limits the range of a reas for mac roinverteb ra tes to c olonise. The hab ita t tha t is p resent is not as stab le as tha t found in the riffle zone and therefore there tends to be less d iversity living in the runs.

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HABITAT GAME

The following pages contain pictures of some macroinvertebrates and two habitats. The pictures can be coloured in.

There are 2 pictures of a habitat one in its natural state and the other polluted. Enlarge the habitat pictures to A3, print and stick them together.

Cut out the pictures of the macroinvertebrates write their names on the back and some interesting information about the critter. Then stick them on the habitat pictures where they like to live e.g. on the bottom of the waterway in unpolluted water. Mosquito larvae can live in polluted water and hang under the surface of the water. You may have to do some extra research.

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