SAMPLING BIODIVERSITY USING

MACROINVERTEBRATESASSESSING AQUATIC BIODIVERSITY

WHAT IS A MACROINVERTEBRATE?

• “MACRO” – BIG ENOUGH TO SEE WITH THE NAKED EYE

• “INVERTEBRATE” – NO BACKBONE

• THESE ORGANISMS REPRESENT THE FOUNDATION OF FRESHWATER AQUATIC ECOSYSTEMS• FOOD SOURCES FOR-

• FISH

• BIRDS

• REPTILES AND AMPHIBIANS

• DIVERSITY OF MACROINVERTEBRATE LIFE IS AN INDICATOR OF STREAM HEALTH

BENTHIC MACROINVERTEBRATES?

• “BENTHIC” = BOTTOM

•MOST MACROS ARE IN THE LARVAL OR NYMPH STAGE OF LIFE CYCLE

• EGG LARVA/NYMPH ADULT

DRAGONFLY LIFE CYCLE

Dragonfly NYMPH

TOLERANCE TO POLLUTION• DIFFERENT ORDERS OF MACROS HAVE DIFFERENT

LEVELS OF TOLERANCE TO WATER POLLUTION:• POLLUTION INTOLERANT- MACROS CANNOT TOLERATE

ANY LEVEL OF POLLUTION- WILL DIE IF EXPOSED• EXAMPLES: MAYFLY, STONEFLY, CADDISFLY

• POLLUTION SENSITIVE- CAN STAND SOME POLLUTION• SCUDS, DRAGONFLY LARVAE

• POLLUTION TOLERANT- CAN LIVE IN VERY POLLUTED WATERS• AQUATIC WORMS, LEECHES, BLACK FLIES

WHY DOES BIODIVERSITY MATTER?

THE MORE TYPES OF MACROS WE FIND

THE HIGHER THE BIODIVERSITY

THE HEALTHIER THE AQUATIC ECOSYSTEM IS

WHAT CAN WE INFER IF WE ONLY FOUND POLLUTION TOLERANT BUGS IN OUR STREAM?

IDENTIFYING MACROS

• DICHOTOMOUS KEY

• USE PHYSICAL CHARACTERISTICS TO NARROW DOWN CHOICES

• YOU WILL GET BETTER THE MORE YOU PRACTICE

PRACTICE IDENTIFYING MACROS

• NUMBER YOUR JOURNAL #1-5

• FOR EACH PHOTO- USE THE DICHOTOMOUS KEY TO DETERMINE MACRO

READY?

#1

#1-StoneflyPollution Intolerant

#2

#2-Amphipod (Scud)Pollution Sensitive

#3

#3-Black FlyPollution Tolerant

#4

#4-Crane FlyPollution Sensitive

Adult Crane Fly-They DON’T Bite!

#5

#5-Dragonfly Pollution Sensitive

SAMPLING METHOD- KICK NET1. FIND A RIFFLE OF A STREAM

2. ONE PARTNER FACES UPSTREAM WITH NET POLES IN STREAMBED, NET OUTSTRETCHED

3. OTHER PARTNER STANDS IN FRONT OF NET, UPSTREAM

4. DISTURB STREAMBED- RUB ROCKS OFF IN WATER, KICK, TWIST FEET, DANCE1. THE POINT IS TO DISLODGE MACROS FROM THEIR HOME INTO THE NET

5. CAREFULLY LIFT NET OUT OF WATER WITH DEBRIS INSIDE, BRING TO STREAM BANK AND LAYOUT FLAT

6. SORT THROUGH YOUR SAMPLE, PLACE SIMILAR MACROS IN ICE CUBE TRAY W/ WATER- ID AND COUNT MACROS

WHERE DO THE MACROS LIVE?

•RIFFLES

•PACKETS OF CLUMPED DEAD LEAVES (LEAF PACKS)

•UNDER AND ON ROCKS

•STREAM BED SEDIMENTS (SAND, CLAY, SILT)

TRY TO SAMPLE SITES WHERE THESE HABITATS ARE AVAILABLE FOR BEST RESULTS

WHAT DO MACROS EAT?

• SHREDDERS- EAT DECOMPOSING ORGANIC MATTER (DETRITIVORES)• CRAYFISH, CADDISFLIES, STONEFLIES

• COLLECTORS- FILTER-FEEDERS AND GATHERERS• NET-BUILDING CADDISFLIES, BLACK FLY LARVA, MAYFLIES

• GRAZERS- ALGAE ON ROCKS OR VEGETATION• SNAILS, WATERPENNIES

• PREDATORS- EAT OTHER MACROS, TADPOLES• HELLGRAMMITES, DRAGONFLIES, DAMSELFLIES

WHY SAMPLE THE RIFFLES?

•OXYGEN ENTERS WATER

•MACROS HAVE GILLS – NEED OXYGENATED WATER

OTHER DATA WE WILL COLLECT

• AIR TEMPERATURE (DEG. C)

• WATER TEMPERATURE (DEG. C)

• STREAM DEPTH (CM)

• STREAM WIDTH (M)

• CURRENT AND RECENT WEATHER- RAINFALL

• TYPES OF MACRO HABITAT PRESENT (CHECK) – LEAF PACKS, SUBMERGED LOGS, ETC.

WHEN IS A GOOD TIME TO SAMPLE?

• SPRING AND FALL ARE OPTIMAL

• BE CAREFUL OF PRIVATE PROPERTY AND HUNTING SEASON

• BE SAFE WHEN WORKING IN WATER

ASSESSING WATER QUALITY

• IDENTIFY DIFFERENT MACROS (SCUDS, MAYFLIES, BLACK FLIES, ETC.)

• TALLY HOW MANY OF EACH TYPE OF MACRO THERE ARE- 6 SCUDS, 2 MAYFLIES, 1 CRANE FLY

• USING THE BIOTIC INDEX ASSIGN A NUMBER (1, 2, 3) BASED ON POLLUTION TOLERANCE

• POLLUTION INTOLERANT = 3

• SOMEWHAT SENSITIVE= 2

• POLLUTION TOLERANT = 1

• ADD UP ALL THE BIOTIC INDEX NUMBERS TO GET STREAM HEALTH SCORE

PRACTICE STATIONS AT LAB TABLES

•CALCULATING STREAM HEALTH SCORE BASED ON SAMPLE STREAMS