definitions Flashcards
Spring tides =
occur when the sun and moon are lined up, so get maximum gravitational pull → maximum tidal range
Neap tides =
occur when sun, earth and moon form a right angle and gravitational effects are minimal
semi-diurnal tides
2 ~equal high tides and 2 ~ equal low tides every 24 h
diurnal tides
1 Low and 1 high tide per 24 h
photic zone/epipelagic zone
~ 0-200m deep
mesopelagic =
deep sea (200m - 1km)
bathypelagic=
> 1km – 4km, also something that lives in the oceans
Benthic =
the bottom of the ocean, hence can be at large depths or shallows, it’s the ocean floor, organisms that live on rocks, piers
Abyssopelagic zone =
4km – 6km
hadopelagic zone (Hadel) =
deepest region in sea, within ocean trenches >6km
Golf stream =
= hot water from Florida moves past Sweden and becomes cold
Coriolis effect =
In a reference frame with clockwise rotation (southern hemisphere), the force acts to the left of the motion of the object. In one with anticlockwise (northern hemisphere) rotation, the force acts to the right
Thermocline =
A zone of rapid temperature decline with increasing depth
Catadromous fish =
spend most of their lives in fresh water, then migrate to the sea to breed
anadromous fish =
= live in the ocean mostly, and breed in fresh water lots of water movement & mixing (wind, currents); highly variable environments; relatively high productivity
Copulatory =
Is like the mammalian fertilisation
Non-copulatory =
Males release sperm, females hold the egg, and fertilisation occurs internally
Polyspermy =
describes an egg that has been fertilized by more than one sperm
protandry =
It can change from a male to female
Planktotrophy =
feeding larvae, Plankton feeding Weeks to months in plankton Cheap, small (lower investment) Ancestoral mode Tend to be better dispersers More species in tropics Hot water favours PK
Lecithotrophy =
Non-feeding larvae Yolk feeding Minutes to days in plankton Larger, less eggs (more investment) Common Can’t disperse for long time – medium spread Mum gives oil resources to LC to help get through larval/plankton stage Chemical defences More species in cooler areas
Spring transition =
day the water becomes down stream instead of upwelling effects
Ballast Waters =
waters to help the boat stable in the storm
Realised niche =
when other organisms are there to kick it out
Fundamental niche
were they can live
Phytoplankton =
freely drifting, photosynthetic (microscopic) cells
Picoplankton =
[0.2 - 2.0 μm]
Nanoplankton =
[2.0 - 20 μm]
Microplankton =
[20 - 200 μm]
Femtoplankton =
<0.2 μm
Mesoplankton =
0.2-20 mm
Macroplankton =
20 -200 mm
Megaplankton =
= 200 -2000 mm
oceanic nekton =
all vertebrate classes except amphibians, many types of bony & cartilaginous fish, some mammals, reptiles & birds (peguin the real Nektonic bird), cephalopods only invertebrates (Octopus, cuttlefish, squid)
holoepipelagic species =
spend all time in epipelagic
meroepipelagic species =
may migrate horizontally or vertically
hermatypic corals =
Hermatypic corals are those corals in the order Scleractinia which build reefs by depositing hard calcareous material for their skeletons, forming the stony framework of the reef
ahermatypic corals =
lack zooxanthellae and does not build a reef
Shelf reefs =
grow on continental shelfs
Barrier reefs =
grow on continental shelf but has a barrier
Class Agnatha =
lack of jaw, lampreys & hagfish
Class Chondrichthyes =
cartilaginous, sharks, skates, rays & ratfish
Class Osteichthyes =
bony fish, coelacanth, ray-finned fishes
aspect ratio (AR) =
= is measure of tail size
Deep scattering layer (DSL)
= common for mesopelagic organisms to migrate vertically at night
What number is dustin martin?
4
abyssal gigantism =
is the tendency for species of invertebrates and other deep-sea dwelling animals to be larger than their shallower-water relatives.
who won the norm smith in 2017 grand final?
Dusty
Mariculture =
generally shallow embayment’s or artificial ponds, Breeding species include many types of fish, molluscs, crustaceans & algae
who won the brownlow medal in 2017?
Dusty
Salinity =
is the total amount of dissolved material in water. Dissolved substances include inorganic salts, organic compounds from living organisms and dissolved gasses. The greatest fraction of dissolved material is seawater is inorganic salts, present as ions.
light attenuation =
is the decrease in light intensity with depth in the water column due to absorption (by water molecules) and scattering (by suspended particulates)
Thermal stratification is =
The situation where the uppermost water mass is isolated from the more dense, colder water below
Source population =
A population that produces recruits for other populations acts as a source
sink population =
a population that receives recruits from another population but exports no recruits
intermediate disturbance hypothesis
= species diversity is maximised under intermediate levels of disturbance
The Southern Oscillation Index (SOI) =
is calculated from the monthly or seasonal fluctuations in the air pressure difference between Tahiti and Darwin. The SOI changes from positive (normal conditions) to negative (which indicates El nino)
A carbon sink is =
An environmental reservoir that absorbs and stores more carbon than it releases
Lateral lines =
are rows of small tubes, open to the water and containing sensory pits sensitive to pressure changes in the water
The rete mirabile is =
A network of small blood vessels
Bycatch =
dont’t intend to catch and not retain
byproduct =
don’t intend to catch but do keep
Recruitment =
(Larval supply x Larval Behaviour) –Post-settlement mortality
Larval supply =
production of larvae x delivery of larvae
anisogamous
sexual reproduction by the fusion of dissimilar gametes of size or form.
isogamous
is a form of sexual reproduction that involves gametes of similar morphology (similar shape and size), differing in general only in allele expression
isomorphic
is a similarity of form or structure between organisms, generally between organisms with independent ancestries, e.g. after convergent evolution.
heteromorphic
Having different forms in different stages of the life cycle. Differing in size or structure from the normal. occurring in two or more different forms, especially at different stages in the life cycle
Direct development
No larval phase
Biggest
Least likely to be widespread
Most investment
More variation in success/recruitment
More common in arctic zones
Pneumatocysts =
Gas bladders in seaweeds for flotation
Allee effects =
Positive density dependence, fitness increases with higher densities. At low population densities, population growth rate decreases due to mate limitations. Reduced competition AND reduced fertility success. only affecting external fertilisation
Oxygen minimum zone =
found at 500m-1000m between surface water and cold deep sea, due to thermal stratification, it is oxygen-depleted water. Water above and below zone has more oxygen
Neritic =
relating to the shallow part of the sea near a coast and overlying the continental shelf. different to the pelagic as that is in open ocean
Pelagic zone
the open-ocean zone and includes all the others zones
fecundity =
the ability to produce an abundance of offspring or new growth; fertility
Hydrographic barrier =
like a current, an invisible wall which restricts the ability of larvae to disperse
El nino =
decreased upwelling = increased temperatures around equator, air warmer and drier, bleaching
El nino is terrible for marine
La nina =
La nina is other extreme = increased upwelling, decreased temperatures
physostome fish =
can change depth quickly, duct to mouth so can gulp air into gas bladder
physoclist fish =
takes longer to take air in gas bladder thus cant dive as quick down
countershading =
Dark on top, light on bottom of fish
contrasting colours
break up outline eg. like a tiger in the jungle of India
development of keel =
= less shadow = invisible
