Life in the Ocean Major groups of organisms

Life in the Ocean Major groups of organisms in ocean Plankton Nekton Benthos

Organisms (in general) Plankton: floaters Nekton: swimmers Won’t deal with these much in this course Comments on fisheries Benthos: bottom dwellers

Plants vs. animals Phytoplankton Carry on photosynthesis Diatoms, coccolithophores, dinoflagellates Zooplankton Consumers Radiolarians, forams, others

PHYTOPLANKTON

ZOOPLANKTON

Time as a planktonic organism Meroplankton vs. holoplankton Part of life as a plankton Part of life as nekton or benthos Examples (oysters, barnacles, crabs, fish egg)

Nekton Many varieties Consider commercial fisheries

Commercial fisheries Changes in last 50 years Overfishing Causes: human population, changes in fishing practices, environmental degradation, poor management. by-catch Solutions: close fishing areas, marine sanctuaries, tighter regulations, consumer choices (http: //www. mbayaq. org/cr/Seafood. Watch/web/sf w_regional. aspx)

Aquaculture A solution to overfishing? Pros and cons

Benthos Rocky shores Tide pools Sand mud Deep sea Coral reefs Just a few examples

Where benthic organisms live Epifuana Live on top of sediments Examples (barnacles, starfish, crabs) Infauna Live within sediments Examples (clams, worms)

Epifauna

Infauna (a, b, c, e)

Why these patterns? Land 86% Sea 14% Benthic 98% Pelagic 2% DISTRIBUTION OF LIFE