BIO 475 Study Guide - Fall 2018, Comprehensive Midterm Notes - Coral, Algae, Zooxanthellae
BIO 475
MIDTERM EXAM
STUDY GUIDE
Fall 2018
Tue Aug 29th
● Gulf stream brings warm water from caribbean to Bermuda
● Bermuda is a sub-tropical location, fluctuation of sea surface temp. 60-87 degree F
● 35 km long 35 km wide
● 70,000 residents
● 150 different islands, 7 main islands
● Bermuda considered a Pseudo atoll
● Originated as a volcano, 100 million years ago
○ Active volcano breaks surface and erupts; lava
○ Calcifying organisms; sponges, clams, worms, corals; builds a reef
○ Reef comes up to surface of water; fringing reef
○ Volcano eventually cools, becoming more dense, and begins to sink
○ Erosion in middle of the habitat creating a lagoon
■ Land,lagoon, reef = barrier reef
○ Land continues to sink and settle, end up with island surrounded by a lagoon and
reef crests on either side; Atoll
Origin of Bermuda
● 100myr, late Mesozoic
○ Volcanic activity laid down alternate layers of lava and ash
○ Cones began to erode
○ Sand and silt was washed out to shelves
● In the Pleistocene
○ Of shell-bearing organisms formed a thick cap of limestone and limy sandstone
○ Added to by the growth of coral colonies
■ Rocks, black/gray/jagged; all exposed rock in Bermuda is limestone or
sandstone, cyanobacteria causes the black coloration.Original volcano
completely submerged.
Topography
● Giant lagoon on N shore → Bermuda Island → South slope shore
● Land formation is considered a ‘karst limestone’ formation
○ Rainwater hits land permeates through, carbonic acid erodes limestone creating
caverns and caves
○ Bermuda has more caverns per square mile than any place in the world.
○ Lowering of the water table allowed air to enter the caves permitting the
formation of drip-rock and calcite stalagmites (ground) and stalactites (ceiling).
○ Sea levels rose again and filled caverns with sea water.
● Remnants of collapsed caverns can be seen around the island, arch formations, stacks,
needles + pillars.
Bermuda Reef
● Island with lagoon in the middle with a bunch of patch reefs in the center. On edge of the
lagoon is a rim reef.
● South shore; fore-reef slope
● Deeper; terrace reef; outermost reef system
● South shore; Boiler reef
find more resources at oneclass.com
find more resources at oneclass.com
○ Small, generally rounded reefs that extend to the sea surface and have waves
continuously breaking over them
○ This makes the water look as though its boiling
Types of Corals
● Scleractinian (Hard Coral)
○ 26 species in Bermuda (72 known )
● Gorgonacea(Soft Coral)
○ 23 species in Bermuda (50 known)
Few species survive because of the colder winter weather, which affects ability to grow
● Low winter temps and reduced daily solar irradiance slows coral calcification so growth
is slower in Bermuda than Carribean
● Highest growth rates are in shore
○ Lower wave energy
○ Increased productivity and associated food availability
Long Term Monitoring
● Monitoring coral cover at specific locations; ex. Hog Breaker
● Looking at hard coral cover, macro algae and gorgonians.
● No drastic ramifications in Bermuda, unlike rest of Caribbean
What we will be doing;
Coral Reef Community Structure
● Lagoon patch reef
● Outer rim reef
● Deeper terrace reef
Things to consider
● Abiotic
○ Wave energy
○ Light (sediment)
● Biotic
○ Grazing
○ Competition
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Gulf stream brings warm water from caribbean to bermuda. Bermuda is a sub-tropical location, fluctuation of sea surface temp. Originated as a volcano, 100 million years ago. Active volcano breaks surface and erupts; lava. Calcifying organisms; sponges, clams, worms, corals; builds a reef. Reef comes up to surface of water; fringing reef. Volcano eventually cools, becoming more dense, and begins to sink. Erosion in middle of the habitat creating a lagoon. Land continues to sink and settle, end up with island surrounded by a lagoon and reef crests on either side; atoll. Volcanic activity laid down alternate layers of lava and ash. Sand and silt was washed out to shelves. Of shell-bearing organisms formed a thick cap of limestone and limy sandstone. Added to by the growth of coral colonies. Rocks, black/gray/jagged; all exposed rock in bermuda is limestone or sandstone, cyanobacteria causes the black coloration. original volcano completely submerged. Giant lagoon on n shore bermuda island south slope shore.
