L10 - Zooplankton 2 Flashcards
Two Non native species
DAPHNIA GALEATA & D. PULEX
must know there are two non native Daphnia that have invaded recently.
Have spread far, wide and fast.
1993 - first invasion detected
2005 - second detection
Unknown effect on food web but they do displace native Zooplankton.
Rotorua lakes and Auckland initially but has now spread nation wide
Effects of invasion: Daphnia Galeata in Lake Puketirini
Highly efficient filter feeders.
Results showing secchi depths improving from mid october onward.. most noticeable towards the end of October when the Daphnia bloomed and filtered out most of the algae.
Rotifer population also crashed as the Daphnia population ‘knocked them out’.
Copepoda: general characteristics
MOST ABUNDANT SPECIES IN OCEAN/ESTURIES
MOST ABUNDANT/DIVERSE GROUP OF ANIMALS WORLD WIDE
CALANOIDS: MOSTLY OPEN WATER
CYCLOPOID: 50/50 OPEN WATER/BENTHOS/PLANTS ETC
HARPACTICOID: PLANTS AND BENTHOS
BIG TROPHII AND PROJECTIONS GOOD FOR PLANKTONIC ZOOPLANKTON
Some copeopoda are carnivorous
Food found by random encounter (oppertunistic)
SEXUAL REPRODUCTION ONLY
EASY PEASY LEMON SQUEEZY
Different males have different legs
helps to keep breeding species specific
Lifecycle simple
Copepods carry eggs externally and when they hatch they look different to adult.
Juvenile go through 5 malts before adulthood/sexual maturity
