spring tide
moon is in line with the sun or directly opposite the sun, stronger tide
neap tide
Sun and moon at right angles, least difference between high and low tides
Oligohaline
0.5-5 ppt
Mesohaline
5-18 ppt
Polyhaline
18-30 ppt
Diadromous
Migrate between fresh and salt water for spawning purposes
True Estuarine Fishes
Spend entire lives in estuaries
Non dependent marine fishes/Dependent Marine Fishes
Commonly found in lower reaches of estuaries but are not dependent on them to complete life cycles/ Dependent Fishes do for at least one stage
Osmoconformers
Cannot regulate their body salinity and die during deluges of rain when caught in intertidal zones
Piscivory
fish eating
mud flats, salt marshes
exposed by falling tides, associated with backwater, bays that allow sediment to accumulate
Aerenchyma
tissue that allows gas exchange when surrounded by anoxic soil
Wrack
rafts of dead spartina
Salt pans (playas)
Sites of former or occasional lakes
mangrals
types of trees and shrubs found in the mangrove forest
propagule
dispersal stage of the mangrove, used to generate new plants
facultative halophiles
those that do not require, but can tolerate high salt concentrations, tolerate high osmotic pressure
Epifauna
animals that live on the surface of the substrate (rock,mud,sand)
holdfast roots
root-like structure at the base of an alga (seaweed) that fastens the alga to a hard substrate like a stone
artificial fish habitats
Habitat that is built by humans (sunken boats, tires, concrete structure)
abyssal plain
very level area of the deep-ocean floor, usually lying at the foot of the continental rise, 6,000 m
Nertic System
on or above the continental shelf and oceanic system beyond the shelf
What is an estuary?
area where freshwater meets saltwater (where rivers enter into oceans)
Approximately 15% of the total worldwide fish catch comes from estuaries. True/False
false 8%
Why do environmental conditions in estuarine systems select for/against some fishes?
The temperature and salinity can change rapidly and fish must be able to adapt rapidly. They must spend considerable amounts of energy to find less stressful areas.
How have estuary systems been impacted by humans?
an increase in pollution has caused an increase in water levels which is reducing estuaries and increasing salt water.
How do water temperatures, salinity, and flows oscillate in relation to riverine discharge?
They change with and increase or decrease in flow as a result of snowmelt or precipitation.
What is the interaction of the estuary and marine systems it relates to fishes?
The fishes must be able to adapt quickly to a change in environmental conditions. It provides a nursery area for young fishes.
In temperate zones, mangrove tend to dominate. True/False
FALSE
Why are copepod fecal pellets an important component of estuaries?
They sink to the bottom and become part of the ooze that serves as food for BMI's.
Discuss the vertical zonation of estuaries—what drives this phenomena?
...
What drives the biodiversity in RITZs? [Hint: there are two factors]
Daily oscillations in the rise and fall of tides.
Discuss drag, pressure, and abrasion as it pertains to RITZs.
Abrasion- particles in suspension scrape delicate structures. Pressure- hydrostatic pressure of breaking waves can crush compressible structures.Drag- impact of water can pull organisms from their attachments to surfaces.
What is byssal thread?
strong, silky fibers that are made from proteins that are used by mussels and other bivalves to attach to rocks, pilings or other substrates
Discuss mechanical and heat stress in RITZ systems.
Mechanical stress includes the fluctuation of water, crashing waves. Heat stress includes, evaporative cooling and circulation of bodyfluids aids in reduction of heat loss.
What structures the distribution of limpets, barnacles, and other invertebrates in RITZs?
limitations of size and shape
Discuss rip tides. What makes beach "foam"? [be able to draw these phenomenon]
a strong current caused by tidal flow in confined areas such as inlets , beach foam is made by wave action smashing diatoms and other phytoplankton
What is the function of barbels?
search the substrate to find prey
What is meant by true fish residents of salt marshes? What is Spartina?
these fish can adapt to highly changing conditions. Spartina is a salt tolerant plant
Why are mummichog important in terms of understanding the coastal zone environment?
They can bury themselves in the mud or flop toward receding water.
Contrast partial/tidal fishes in marsh systems [include their respective global locations]
Partial are associated with marshes for only part of their life cycle, tidal are typically larger fishes that invade the flat and feed on abundant juveniles.
What environmental factors structure marsh ecosystems.
Wherever sediment accumulates and is bound and stabilized by vascular plants.
Why are fiddler crabs important in marsh systems?
They aerate and stabilize sediments
Sediments in salt marshes tend in relatively oxygenated. True/False
FALSE
What is the main mechanism of salt marsh plant diversity? [Hint: slide 62]
competition
What type of zonation exists in salt marsh systems?
Vertical
Explain the evolution [from a varying plant perspective] that leads to Spartina [Hint: examine slides 62-66]
They are more evolved than other species in high marsh and low marsh areas.
What role doing grazing snails have on Spartina? What are they consuming? How do these snails structure some marsh plants? Which organisms consume these snails?
The snails are feeding on fungi which are feeding on the leaves of the plant which are rich in cellulose. These snails keep the plants healthy from the fungus. crabs and terrapins consume the snails.
What are some the ecosystem services provided by salt marshes?
Flood runoff, carbon sink, and nursery grounds from commercial and recreational fish and shellfish
Why are mangroves found globally? What limits their distribution?
they are a tropical and subtropical plant that is sensitive to freezing so their distribution is limited.
Mangroves tend to thrive in zones with relatively significant wave action. True/False
FALSE
How do mangroves "grow" islands?
their root systems are very large and can trap sediment forming islands.
What are pneumatophores and salt glands? How do these structures function?
Salt glands excrete salt to maintain osmotic balance in the cells. pneumatophores are aerial roots that are used for gas exchange
Contrast drop and prop roots [be able to draw].
prop roots rise from the stem and are used for support. drop roots are roots that drop from the branches not attached to the earth, when they attach they are called prop roots.
What don't mangroves do well in FW?
They don't compete well in freshwater. saltwater gives them refuge from other competitors.
Why are mangrove crabs important in maintaining mangrove canopies? [Hint: are two major roles]
Mangrove crabs eat beetles that are possibly dangerous to the trees and they make burros that oxygenate the soil
Mangroves tend to be P-limited. True/False
FALSE
What is the importance of the drop down roots systems in mangrove forests?
They allow the breakup of waves to help stabilize the tree.
Sea grass beds are relatively low in biodiversity because of...
the environmental fluctuations in salinity and temperature limit biodiversity.
Young fishes often use sea grass beds as nursery areas. True/False
TRUE
Fish numbers in grass beds tend to be highest in daylight. True/False
FALSE
Under optimal conditions kelp can grow up to _____ a day.
.6 m
Where are kelp forests located globally?
temperate waters between 6 and 30m
Why do great whites often invade kelp forests?
sharks use the forests for feeding areas because the forest is used as a safe zone and cover.
Why is time of day any important consideration in experimental design of fish communities?
Fish tend to be more active at dusk, dawn, and night hours because of the limited light for safety and feeding purposes.
The southern hemisphere is ~ 71% oceanic. True/False
false 80%
Contrast benthic vs. pelagic
Benthic- refers to fishes that live near the bottompelagic refers to fishes that reside in the open ocean
Where is the Southern Ocean?
surrounds Antarctica
What are the four oceanic basins?
Atlantic, Pacific, Indian, Arctic
What are the five pelagic [and benthic] zones we discussed in class?—include relative depths
Pelagic- Epipelagic <200m, Mesopelagic 200-1000m, Bathypelagic, 1000-4000m, Abyssopelagic, 4000-6000m, Hadopelagic >6000mBenthic- Shelf <200m, Upper Slope, 200-1000m, Lower Slope 1000-3000m, Abyssal Plain 3000-6000m, Hadal Zone 6000-11000m