Transcript competition for space fierce (limiting factor)

ROCKY INTERTIDAL ZONE
Western US rocky intertidal zones –
less seasonal changes.
The greatest limiting factor is space.
Eastern US soft-bottomed intertidal zones - temperature changes
cause seasonal population changes.
The greatest limiting factor is climate.
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Rocky coasts are characterized by:
- abundant food supply with good
light
- tides produce hours of flooding in
cool water followed by desiccation
(drying out) and high temperatures
- tidal pools are created and
emptied
- temperature and salinity fluctuate
- very distinct zonation worldwide
- wave shock
http://www.youtube.com/watch?v=6pZ0PZBNgU4
- competition for space fierce (limiting factor)
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COPING STRATEGIES / ADAPTATIONS:
- WATER LOSS:
- run & hide, clam up, tolerate
- allow drying out
- find tide pools
- http://www.youtube.com/watch?v=6QaMA5S1E1E
- http://www.youtube.com/watch?v=IyNEG-PvZmM
- TEMPERATURE
- tolerate
- move to moist areas
- light color
- SALINITY
- clam up
- tolerate
- RESTRICTED FEEDING (MOST ARE FILTER FEEDERS)
- only feed when tide is high
- tide height determines where they can live
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COPING STRATEGIES / ADAPTATIONS:
- WAVE SHOCK:
- attach (holdfasts, byssal threads, glue)
- cling (suction cups)
- fish lack swim bladders
- find shelter
- thicker shells
- compact shape
- low profile
- go with the flow / flexible
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Wave action cuts rocks into
sea caves, cliffs and sea
stacks that provide shelter.
Competition for these limited
living spaces is high.
Inhabitants must find a place to attach or hide or be crushed
between waves and rocks.
Methods of attachment include cement, byssal threads,
holdfasts, muscular and tube feet, and boring.
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Adaptations also include symbiosis and reproductive strategies,
like hermaphrodites and organisms that change sex.
NOAA
The rocky coastal communities’ succession has a predictable
pattern that is often controlled by sea urchins. Grazing urchins
remove algae from rocks.
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New communities can then begin because one group doesn’t over
populate the area.
Pioneer stage bacteria and algae
Juvenile - protozoa
and worms
Mature - barnacles,
rockweed,
mussels, seastars
and sea urchins
Collectively these animals became known as fouling
communities because of their harmful effects on ship’s hulls,
docks, pilings, and the smell they create at low tide.
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THE BATTLE FOR SPACE
- AVAILIBILITY OF SPACE LIMITS
POPULATIONS IN INTERTIDAL
- COMPETITION FOR SPACE
DOMINANT BIOLOGICAL FACTOR
- HOW TO COMPETE
- be first to get to open space
- effective dispersal
- reproduce rapidly
- take over
- grow over
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VERTICAL ZONATION
- UPPER, MIDDLE & LOWER
ZONES
- UPPER LIMIT SET BY PHYSICAL
FACTORS
- LOWER LIMIT SET BY BIOLOGICAL
FACTORS (predation & competition)
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