exam 2 Flashcards
1
Q
continental shelf
A
extends out into the ocean and the steep drop is the slope
2
Q
abyssal plane
A
about 600 m down and very high pressure and an overall extreme environment
3
Q
photic zone
A
the zone where active photosynthesis takes place
-up to 200 m down
4
Q
features of antarctic continental shelf
A
continental shelf is very narrow, but also deeper than other continents (about 500 m)
-helps to isolate the continent and keep it’s life endemic
5
Q
how much of antarctic life is endemic
A
80%
6
Q
benthic biodiversity in Antarctica and endemism
A
the benthos has surprising diversity
-sea stars, scallops, sponges, urchins, clams, and bivalves
7
Q
sea ice and nutrients
A
sea ice complicates the photic zone in the winter
-reduces light penetration
The ice has cold saline water below it which sinks and this water is very nutrient rich from the algae in the sea ice.
when upwells increases productivity around antarctica
8
Q
pyconogonids
A
sea spiders: they are very diverse in the bathos
-more so than anywhere else
9
Q
bull kelp characteristics
A
each lengths greater than 20 m
-strongest in the world to sustain themselves in heavy seas
10
Q
kelp community in antarctic peninsula
A
has the highest diversity of the inshore marine environment
-more than 90 species
and is a nice bed for seals
11
Q
what species are in the Antarctic Peninsula kelp
A
worms, mites, sea-stars, sea-cucumbers, and numerous curstaceans
12
Q
biological pump in ethic zone
A
carbon is sequestered/trapped in the benthos for hundreds of years by dead singing algae/datoms/etc
13
Q
king crab invasion
A
Inshore waters are colder than deep waters due to the katabatic winds and circumpolar current, but the average water temperature has increased by 1ºC. This change caused more CO2 dissolved, change in chemical pathways and lower pH. Change in water temperature is a slow process. The Antarctic Peninsula is now 9ºC in the winter. Cold water limits diversity to endemic species, but the warming trend allows other species to invade.
14
Q
potential impact of king crab invasion
A
devastating to certain species and change the community structure because many of the animals here haven’t developed a defense against this animal
15
Q
sea ice algae
A
sea ice formation in the late summer traps marine algae in pockets of brine. the algae remains dormant through the winter. when the ice begins to melt in the spring it acts as a greenhouse and algal growth occurs. when ice fully melts, algae released into water which stimulates food chain.
16
Q
what is the relationship between sea ice, algae, a nd krill
A
thicker ice means more algae and so more krill
17
Q
heavy vs light ice years
A
heavier ice means more brine, which means more algae, which means higher productivity
18
Q
why more ice with warmer temps
A
2012 was a heavy ice year, but also one of the warmest on record. The warmer air caused an increase in the katabatic winds which caused an increase in sea ice formation.
19
Q
sea ice microhabitats and community
A
Melt channels in the ice have bacteria/worms due to the brine that grazers can gain access to. Sea ice is dominated by small pennate diatoms.
20
Q
primary production and timing in new vs multiyear ice, marginal ice zone
A
Primary productivity peaks in sea ice in November (summer) before it peaks in the marginal ice zone/open water as it is primarily annual ice (perfect timing for productivity due to reproduction in summer). Multi-year ice peaks later due to light blockage (snow accumulation).
21
Q
antarctic krill
A
keystone species bc fed on by penguins, fur seals, and balloon whales. Dependent on the algae in sea ice. Productivity is essential for the food chain
-can cause a bottom-up cascade
Found in the Antarctic Peninsula
22
Q
krill life cycle
A
spawn in January-march laying eggs at surface which sink 2000m. eggs hatch after 10 days, larval krill grow and move up the water column. Adult krill live 7-9 years
23
Q
vertical migration in krill
A
can track krill cohorts through penguin diet sampling
24
Q
crystal krill and how it differed from antarctic krill
A
Crystal krill are smaller than antarctic krill. They’re more southern (74º latitude and higher). The eggs don’t sink. Larval and adult forms occupy the same shallow water associated with sea ice.
25
krill swarms
Krill are abundant but only in patches. They occur in large swarms and filter feed on algae and diatoms. Fed upon by fish, seabirds and whales (500 million tons). They can rake algae below the sea ice (one krill can rake 1 ft2 in 10 mins).
26
slap and patterns in abundance
years, but are not as edible to other animals due to their low nutritional value. They live only one year, with a few vertebrate predators. Their intense grazing of algae deprives krill of food. Add to the biological pump.
27
ice fish
- dominant group of deep continental shelf, with over 100 species
- mostly endemic to Antarctica and adapted to cold water and the benthic zone
28
Nototheniodei characteristics in ice fish
- have no swim bladder and therefore no buoyancy.
| - Produce antifreeze glycoproteins
29
antifreeze glycoproteins
```
class of polypeptide that bind to ice crystals preventing them from expanding
-several types developed independently first were isolated/described in antarctic fish
```
30
silverfish
Common in penguin diet (larval form). Larva form at the surface during summer within penguin diving limit. They are high in abundance around/under sea ice. They are another key stone species. They spawn and migrate to deeper waters and live up to 14 years. Adults can be fed on by seals and orcas.
31
channichthyida fish and characteristics
They have less than 1% hemoglobin in their blood and absorb oxygen in the water column through their skin. They have no scales, or swim bladder. They are transparent.
32
otoliths
ear bones made of outline and CaCO3
| -shape and size are district by species & can be used to estimate fish size
33
why is studying otoliths relevant
when they are found in penguin stomachs/guano they can indicate diet quantity. They have oxygen isotopes that preserve well in guano that can be used to indicate water temperature over time
34
Deep sea benthos compsosition, orgin, and biodiversity
not as isolated as the continental shelf therefore has a higher diversity. The fauna is not limited to endemic species only
35
ANDEEP program
Program to target deep sea benthos in the southern ocean between 2002 and 2005.
36
Biodiversity pump from Ross and Weddell seas
Research done with gene flow in bipolar foraminifera indicates that many species may have originated from the continental shelf and evolved in the benthos.
37
why is gigantism more common in marine inverts in Antarctica than anywhere else on the planet
The water is extremely cold and therefore oxygen rich. though oxygen exchange is slower, and therefore the inverts need less of it.
38
biodiversity in west vs east Antarctica
Less than 2% of the continent is snow/ice free, and these are the areas where the terrestrial life is. Diversity is more limited in east Antarctica due to the harsh conditions. The AP has a milder climate, more precipitation, more moss/algae and the only two flowering plants on the continent.
39
Soil characteristics
soils provide a substrate and are teeming with life.
- are a living ecosystem and a supergoranism filled with thousands of miorganisms
- -inclludes minerals, water, gases, and organic matter
40
five processes for development of soils
1) Parent material (bedrock adds nutrients to the soil that affects vegetation type)
2) Climate (relates to weathering rates)
3) Vegetation (dependent on nutrients from bedrock)
4) Topography (high points are soil-limited)
5) Age (it takes time for soil characteristics to develop)
41
soil horizons
O - surface leaf litter
A - nutrient rich/dark
E - zone of leaching (water percolates through carrying nutrients)
B - zone of accumulation (water evaporates leaving nutrients)
C - weathered parent material
soil horizons can be indicative of climate (thickness and depth depends on water percolation and soil texture)
42
parent material importance and breakdown
The parent material provides the nutrients.
| -breakdown can be physical (exfoliation) or chemical
43
granite parent material
has varying elements that provide rich nutrients to the vegetation.
44
serpentine parent material
less nutrient rich which leads to limited plant growth
45
exfoliation
Water seeps into cracks and rocks and expands them via freeze/thaw action. Over time pieces break off.
46
gelisols
Permafrost affected soils (soils below zero temps that aren't frozen). This is due to the fact that there's no moisture in the soils keeping them loose. Unique to the Antarctic.
47
ornithogenic soils
Bird formed soils
| -hugely Adelie penguin pebble build up
48
how are ornithogenic soils formed
Adelie penguins build their nest with pebbles of similar shape/size year after year. newly formed soil is moist due to guano/waste in the mom. Once the colony is abandoned the soil dries out and becomes red in color due to krill in their diet
49
what are ornithogenic soils rich in
organic materials (feathers, bones, eggshells, prey remains) that preserve extremely well
50
why are ornithogenic soils extensively developed in antarctica
due to Adelie penguins/permafrost conditions
51
Microfauna in antarctic soils
Organisms in the soil range from microfauna (bacteria, fungi, protozoa) to macrofauna (tardigrades, mites, nematodes)
52
what is the largest terrestrial predator in antarctica
mites/springtails
53
Adaptions of tardigrades springtails and nematodes for antarctica
- Tardigrades, springtails and nematodes super cool below freezing temperatures.
- Nematodes can expel water from their cells under extreme conditions.
- Nematodes/tardigrades can dry up, blow away, and then come back to life.
54
cryoturbation and polygons
Characterizes antarctic soils. Formations can be formed from freeze-thaw. Polygons are naturally formed through cryoturbation (mixing of materials due to freeze/thaw) in deep soils.
-Big and small, sometimes small in big!
55
freezethaw
pushes larger rocks to the edge of the formation and the formations are buit up over millions of years
56
cryptogams
seedless/flowerless plants that reproduce via spores
57
cryptogamic soils
characterized by cryptogam plants. A crust forms on top of the soil that covers with lichens, fungi, or bacteria that can give gas exchange (N or C) to the soil and stabilize it
58
Dry valley soil characteristics
East antarctic soils are poorly developed, barren, dry and low in nutrients. This is due to the fact that there are no plants/water percolation due to the fact that water is frozen. The extreme conditions only allow for moss, algae and lichen growth.
Many soils were formed from fluvial activities in the past. They can be millions of years old, but still lacking in structure.
59
antarctic peninsula soil characterisistcs
The AP is lower in latitude, has warmer temps, a more maritime environment and has 20-100 cm of precipitation.
More moisture means more organic content going into soil, more horizon development with drainage.
There are two flowering plants, more inverts and many soil types on the AP.
60
three types of lichens
crustose-form crust over substrate
Folios-leaf like
Fructiose-bushy
61
mutualism of fungi and algae
The fungi protect the algae from the harmful UV radiation, while the algae fix nitrogen for the fungi.
62
Lichen biodiversity and characteristics
AP: ~150 species, mostly crustose, fructicose lichen garden on livingston island
EA: ~60 species, higher diversity found at colonies where nutrients facilitate growth (biological hotspot)
63
Lichen growth rates and reproduction
There's a fructicose lichen forest at eye level. Foliose lichens on lagoon island that can grow in the right micro-climate. Lichens exhibit slow growth. They reproduce by small pieces breaking off/animals carrying them/reproductive spores. The spores find algae and grow. Pigments prevent them from freezing down to -10ºC (can still photosynthesize). The farthest south they are found is 87º09'S
64
endolithic lichens
Inside mainly sedimentary rocks. They are adapted to UV radiation, ice cold winds and scouring. They are about 1 cm down in the rock. The orange layer is precipitated iron, the green layer is the algae and the black layer is the fungi. The fungi still protects the algae from UV but little is known about the mutualism in this ecosystem otherwise.
65
Moss biodiversity and algae characteristics
They occur in wet or moist areas. They are restricted in distribution/diversity to about 100 species of moss in snow melt areas. Stems are adapted to the cold in that they are tightly packed to prevent water loss/freezing. Snow coverage prevents scouring. More moss might occur in smaller/low/wet areas, but won't recover easily from a footprint. Moss beds can grow like a carpet over the beach (due to wind/animal disturbances on the AP) and can grow/recover faster.
66
moss pigments and photosynthetic physiology
Different pigments indicate diverse photosynthetic physiology, which is why there's more than just green moss on the continent.
67
snow algae characteristics, mucilage
Some red/green algae grown on snow. They probably evolved from aquatic algae. Their cells produce mucilage which coats/protects them and allows them to bind to each other to block some UV radiation.
68
antarctic grass and pearlwort distribution and characteristics
They are found only on the AP. They grow thick over penguin colonies (guano causes more growth) Grasses and other plants are extensive over the AP where nutrients are rich from animal waste/guano. The grasses have been expanding due to substrate opening up because of higher temps causing more melting. This could be a good thing because they sequester some carbon (small amount though)
69
biodiversity trends for plants and inverts sub-antarctic to the continent
Diversity decreases from sub-Antarctic to maritime (AP) to the continent.
-diversity drops as temperature drops
70
why ornithogenic soils mainly in Antarctica
these soils are rare outside the polar region. they are preserved extremely well in Antarctica, and have a definitive lithology from the Adelie penguin pebbles (not in the arctic)
71
Formation with age and lithology of ornithogenic soils
These soils are characterized by a specific lithology due to penguin nesting behavior. Males return to the same site year after to year to clean it out and rebuild it with pebbles of similar shape/size. These pebbles protect the eggs from rolling away/the water. Thousands of pebbles are added to the penguin site each year. Young still-developing soil is dark/moist due to the guano and waste. It can take 500 years to dry out (reddish hue due to krill in their diet). Th enriched nutrients from the guano in the soil increase vegetative growth. When the soils dry they maintain the smell of guano. Gravel terrace and interface is below the organic material.
72
biological archive preservation
The soils preserve organic material extremely well. Organic material includes mummies, bones, eggshells, feathers, otoliths, squid beaks, other prey remains. Though bones may get ground up from freeze-thaw eggshells usually preserve.
73
types of analysis possible from ornithologistgenic soils
Radiocarbon dating - occupational history
Ancient DNA - evolutionary rates
Stable isotope - how diet responded to climate changes
O2 in ottoliths - temperature changes of sea water
74
where has the longest record of Adelie penguins
The Ross Sea has the longest record of Adelie penguins (some older than radiocarbon dating.
75
microbiota compared to other soils
At active penguin colonies 92% of all biomass is bacteria. There are no tardigrades and only one type of nematodes/springtails. High salts, high concentration of toxic nutrients and a low pH limit macrofauna diversity.
76
algae associated with penguin colonies
There is no vegetation within the colony due to trampling by the penguins. There is, however, moss/algae growth on the outside edge of the colonies (nutrients from runoff from the colony). Once the colony is abandoned plant biomass from the outside fills it in (very different than the natural landscape). Lichen growth occurs over ancient colonies on the pebbles.
77
ornithogenic soils vs ornithogenic sediments
The soils are physically built up by the penguins in the colony. The sediments are runoff from the soils in a low spot. The sediment accumulation won't have the same lithology, but will have the same nutrient/elemental content.
78
bioelements in ornithogenic soils and sediments
Penguins bring offshore elements onshore through their prey deposited in their guano. The elements have a distinct profile in the soils/sediments. They can add nutrient richness to the soil.
79
estimating past penguin populations and movements from bio elements
Bioelements can be used to assess past population/occupational history through coring.
Cape Bird: lots of abandoned colonies between active ones, coring indicates that there was a possible migration route during 1300-1400 AP with changes in local conditions at the time.
80
important factors for lake mixing/productivity
1) Geography/topography (wind shelter? constant temps?)
2) Nutrient inputs (allochthonous vs autochthonous)
3) Size (how much wind is needed to mix the lake)
4) Age (sediment build up can affect depth/dynamics/light attenuation affects photosynthesis)
81
why do lakes differ
they are closed systems and nutrient sinks. differ due to nutrient supply (CO2 & O2 can diffuse/photosynthesize from air/water/plants), and how nutrients come up
82
dimiiic, monomictic and meromictic
Dimictic lakes mix twice a year (bringing nutrients to algae)
Monomictic lakes mix once a year (Anatarctic in summer)
Meromictic lakes seldom mix due to permanent stratification (constant temps, no wind, or ice-coverage).
83
Oligotrophic
Oligo: hypolimnion is larger than the epilimnion, less allochthonous input, less decay in benthic, oxygen increases with depth, lower productivity
84
eutrophic
hypolimnion is smaller than the epilimnion, more allochthonous input, more decay in the benthic, oxygen decreases with depth, more productivity
85
what does productivity refer to
amount of new tissue growth per year
86
allochthonous vs autochthonous input in lakes
Allocthonous input are nutrients from outside sources (runoff, rain, etc) whereas autochthonous input are the nutrients (C, O, N) added by autotrophs.
87
lake types
1) Freshwater
2) Saline
3) Epishelf
4) Supraglacial
5) Subglacial
88
lake characteristics
- most monomictic and ultra oligotrophic
- found in ice free areas and even 4 km below ice
- range from small ponds to large bodies of water
89
how were lakes in Antarctica initially discovered
During the British discovery expedition 1901-1903 by Robert Falcon Scott. Early focus was on algae, algal mats, crustaceans and protozoans along with the physical and chemical environments of the lakes
90
effect of ice cover on lakes
Ice cover further limits productivity. Less light penetrates the lake due to snow and ice cover/thickness which reduces photosynthesis.
91
percent salinity for Freshwater lakes vs saline lakes
Freshwater lakes need to have a salinity less than 9% the concentration of sea water, whereas saline lakes need to have 9% or higher.
92
freshwater lakes
Most freshwater lakes start as saline lakes and are the most common. Most are monomictic and ultra-oligotrophic. Many stations use these as water source which changes the lake dynamics.
93
Lakes at penguin colonies
They have a greater productivity. Snow melt will enrich the lake with allochthonous input from guano. The bioelements build into a stratification that can be cored to learn about penguin history.
Small growth regardless of allocthonous input due to other limits.
94
dry valley lakes and variations
There are many lakes in victoria, wright and taylor valley. Lake vida is frozen to the bottom year round with very little known. Lake victoria is similar to lake vanda. Most lakes have some semblence of snow coverage restricting productivity.
95
Don Juan pond (significance/source of CaCl2 salts)
The most saline lake on Earth. It was discovered in the 1960s via helicopter. It's 10.0 cm deep and needs to be -50.0ºC to freeze. The terrain around the lake has dark spots with dissolved CaCl2. The CaCl2 sinks into the ground and travels into the lake over time. There is some extremophile bacteria in the lake.
96
Lake vanda
Has transparent ice on top which allows for more solar radiation and warming below the ice with liquid water below. There's photosynthetic plankton at the surface under the ice, cyanobacteria at the bottom, and algae on the sides where it melts a little in the summer. It's meromictic, ultra-oligotrophic and phosphorous deficient.
97
Lakes Bonney, Hoare, and fryxell
Located in the Taylor valley, Canada glacier separates Hoare from Fryxell. Bonney and Fryxell are saline, whereas Hoare is freshwater. Bonney is snow/iced over but reaches 3.5ºC in the summer which allows some melting. Hoare is permanently iced over with only 1.7-3.3% light penetration.
98
ross ice shelf, lake Washburn, and evolution of dry valley lakes
Past ice shelf movement blocked in the dry valleys causing lakes. Meltwater from the glaciers filled Taylor valley creating lake washburn 9500 ya. The lake begun evaporating causing a salinity variation 7000 ya. Lakes Hoare/Fryxell separated from Bonney 5000 ya. Canada glacier separated Hoare from Fryxell 3000 ya. (known through coring data)
99
biota in freshwater
Bacteria, viruses, protozoa, phytoplankton (algae and photosynthetic bacteria), zooplankton (clydocerans, rotifers and copepods), cyanobacterial mats in benthos.
100
cyanobacterias mats
Community consisting of photosynthetic cyanobacteria, bacteria and diatoms that also fix nitrogen. They form layers/columns and often occur in fluctuating and extreme environments. Though, they still need enough nutrient input and light penetration.
101
rotifers, cladocerans, and copepods
Zooplankton sometimes found in freshwater lakes.
102
Saline lakes
Defined as salinity of 9% the concentration of sea water or greater. They are usually closed with an inflow of NaCl and CaCl2 but no outflow.
103
two ways saline lakes form
1. They can form when a lake is initially separated from sea level. Then the sea level rises and opens the marine basin. When the sea level drops, the original lake has higher salinity.
2. Another way it can form is through water loss via evaporation increases salinity. Glacial melt lowers salinity. Productivity can be higher compared to freshwater lakes. They are meromictic due to the salinity causing permanent stratification.
104
stratification in saline lakes
Meromictic lake with a saline anoxic monimolimnion (with photosynthetic sulfur) below a colder, less saline oxic mixolimnion (phytoplankton).
105
pony lake characteristics
Located on cape royds on ross island. It's FW in the summer with ice melt, but saline in winter with ice formation (at 9% boundary).
106
epishelf lakes origin
Freshwater systems overlying seawater or with a direct connection to the sea. This is either a direct entrance below the ice shelf (most common) or a tidal conduit beneath the ice shelf/glacier.
107
why epishelf lakes
These lakes are almost entirely restricted to Antarctica because the arctic is losing ice shelves.
108
Epishelf lakes diversity
FW biota and marine fish/organisms
109
beaver lake
It's seven miles long with permanent ice cover. It receives glacial melt water with more more dense marine water below. The biota includes strictly marine species of fish at the bottom with freshwater diatoms at the surface waters. Little is known about C cycling/specie diversity.
110
superglacial lakes and characteristics
They range from small ponds to larger lakes (km2). They are shallow, short-lived and low in biota diversity. Some have deep holes that connect to the sub-glacial hydrological system. They can also be found on ice shelves at ablation zones.
111
cryconite holes
Moulins form from wind blonw dust, soot and microbes on glacial surface. The dark coloration absorbs heat and melts ice.
112
subglacial lakes, how they're discovered and mapped
Lakes that exist below glaciers. Hundreds are now known, most are small (<10km in length). They were first discovered in the 1960s using radio-echo sounding. They're isolated for millions of years from the atmosphere receiving no light.
113
how are subglacial lakes formed
from ice regelation and are fw or saline depending on the bedrock
114
lake vostok research
Lake Vostok is the largest (250 x 50 km) best known subglacial lake (4 km down in the glacier). It has another 300-400 m of sediment on the floor and hasn't been exposed in 14 millino years.
115
lake Vostok recent results from Russian core
Russians cored the lake in 2013, but there's possible contamination due to kerosine. The apparatus siezed/stopped at the accretion ice. They found ancient bacteria.
116
blood falls
Located in Taylor valley, it's a subglacial lake with water forced up from the lake through a vent release. The water from the bedrock is high in iron and turns bright red from interactions with air.
117
Subantarctic islands: how defined and locations
The islands are north of the antarctic convergence, and in the path of the westerlies (affect vegetative growth).
118
Scotia arc and island chains
The scotia arc is a chain of islands around the tip of South America. This island chain is only one linking Antarctica to another country. The islands are located on the edge of a plate that formed when Antarctica Split from Gondwana. The Antarctic peninsula is an extension of the Andes.
119
biodiversity and climate
Anything above the antarctic convergence will have milder conditions and a higher diversity. The climate is dominated by the westerly winds, 25-30 in of rain/snow (due to the islands being in a low pressure system). Some islands have mountains with permanent glaciers. Cold-water upwelling means high marine productivity. The islands are tussock-grass community dominated, and support most of the world's seabird/seal populations.
120
Isla del los estados
Isla des los estados has some woody vegetation due to northern locaiton.
121
South Georgia island
South georgia island is long, narrow, an extension of the andes, and one of the larger islands. The first shots of the falkland war were fired here. Hundreds of thousands of penguins, seals and fur seals breed here. It has a rich tussock grass community.
122
south George island animals
Reindeer were introduced for food in 1911, rats arrived via ship accidentally at whaling stations in 1909-1917. The island is still recovering from human impacts. King penguins are extremely abundant.
123
antarctic maritime islands
These islands are south of the antarctic convergence. South sandwich island has similar vegetation to the antarctic peninsula and low diversity.
124
human impacts
Whalers and sealers not only intentionally/accidentally introduced species (messed with the natural wildlife dynamics), but they hunted many species to near extinction for their fur/blubbler (including seals, whales, and penguins).
125
tussock grass community
Clumps of grass on a fibrous pedestal. They are adapted to high salts due to sea spray. It forms a habitat for many birds/inverts. The birds use it to burrow/sit on. The soil is so acidic peat builds up (growth rate > decay rate). They are restricted to a narrow band around the coast. Smaller and less dense inshore as they're intolerant to higher altitudes.
126
bird guano and volatilization of nitrogenous compounds
Tussock grass communities receive most of their nutrients from bird guano (addition of biolements). The mixture of sea spray, higher temps and bird guano volatize nitrogenous compounds that spread out over the entire community.
127
introduced species and impact
Introduced species can be large mammals to smaller species (mice, rats, cats, pigs, goats, reindeer). They can cause considerable damage to the tussock community and are difficult to eradicate.
128
introduced species on Marion island
Marion island is mountainous and owned by south Africa. Mice were accidentally introduced by sealers. They fed on the vegetation, invertebrates, and seabird eggs. They are highly tolerant so they expanded everywhere including high altitudes. In 1949 they introduced cats to eradicate the mice. By 1977 there were 3400 cats devastating burrowing seabird populations. They eradicated the cats by disease/hunting/trapping. By 1991 the mice came back and are devastating albatross population.
129
introduced species on south Georgia island
Reindeer were intentionally introduced in 1911 for food. They've grazed so intensely that the grasses may not be able to recover from erosion. They are easier to eradicate due to their large size.
Rats were accidentally introduced by whalers in 1909-1917. They are devastating to the ground nesting birds including an endemic songbird, petrels, and penguins. IN 2011 we dropped a poison to make them fear the sunlight, burrow, and die. It is the largest eradication effort.
130
introduced species on Macquarie island
Eradication of rodents/rabbits began in 2007 but the poison was also killing seabirds. The cost/effort was extremely high to search for and kill the last few. Efforts were finished by 2014 and the island is pest free.
131
South Georgia pipit
Most southerly nesting songbird. First nesting record in living memory in 2015 after the rats were eradicated. They are making a nesting comeback.
132
Macquarie island
1. Australian owned one of first affected by sealers and whalers for fur and blubber
2. island more isothermal with equable temperatures year round with averages 4-10
133
why is Macquarie island special
only place mantle rocks are exposed above sea level, and is located at the edge of two plates (Australian nd pacific)
134
Macquarie animals
thousands of penguins and fur seals (only place royal penguins breed) 3.5 million breeding seabirds of 13 species inhabit the island
135
Douglas Maws and Macquarie island
Mawson used the island as base in 1911-1914 before going to the Ross Sea. He noticed the damage (near extinction of species), and lobbied Australia for protection of the island. Sealing licenses were revoked in 1916, and the island became a sanctuary in 1933. A permanent scientific station was established in 1918. It was designated a world heritage site in 1997.
136
MPA and effectiveness
New zealand established an MPA around Bounty, Antipodes, Campbell and Auckland. They are zones extending into the ocean that are vital for an island's success, and are becoming more common. Permissions are needed to enter an MPA. Australia has an extensive network but it's debated due to politcal/fishery agendas. UK has one on South Georgia & South Sandwich to limit krill/toothfish fisheries.
137
five features of successful MPA's
1. enforcement
2. discrete area defining
3. complete fishing ban
4. long term establishments
5. size must be large to protect most amount of species
