HydroidsHydroids

Kelly CohenKelly Cohen

A Colonial AnimalA Colonial Animal

Hydrozoa classHydrozoa class ““small predatory animals”small predatory animals”

Live in the intertidal & subtidal Live in the intertidal & subtidal zoneszones

Individual polyps all connected Individual polyps all connected create create a single organism a single organism

Closely related to jellyfishClosely related to jellyfish

What do they do?What do they do?

They form colonial homes They form colonial homes Ex: for hermit crabsEx: for hermit crabs

TuburliaTuburlia is not colonial is not colonial ObeliaObelia attaches to rocks, seaweeds, attaches to rocks, seaweeds,

substratessubstrates Made of feeding polyps & reproductive polypsMade of feeding polyps & reproductive polyps Similar lifestyle to jellyfish & sea anemonesSimilar lifestyle to jellyfish & sea anemones

Can cause skin irritation when rubbed Can cause skin irritation when rubbed againstagainst

Portuguese Man-of-WarPortuguese Man-of-War

““very much feared”very much feared” A colony made up of many types of A colony made up of many types of

polypspolyps Very painful sting, can be fatal!Very painful sting, can be fatal! Its polyps are actually very usefulIts polyps are actually very useful

One allows it to float (looks like a sail)One allows it to float (looks like a sail) One makes up the stinging tentaclesOne makes up the stinging tentacles Some kill & digest foodSome kill & digest food Some contain the reproductive functionsSome contain the reproductive functions

Hermit Crab Hydroid Research

http://www.youtube.com/watch?http://www.youtube.com/watch?v=0fTdZYaNMF8v=0fTdZYaNMF8