Tasmanian Fauna

[Jeremy]

Lecture 1

Intro

Some examples of Tasmanian Fauna;

Tasmanian Devil; Sarcophilus harrisii
Is the world's largest marsupial carnivore. Weighs up to 12kg. Significant decline over the last 14 years but still fairly common. Mating season is March and young are born 21 days after mating in April. Young are weaned after 5 to 6 months. They are mainly a scavenger and feed on whatever is available. They are useful for cleaning up carcasses in the bush and on farms, this helps reduces things like fly strike. They are nocturnal and can travel long distances in a night. They are listed as vulnerable to extinction due to the devil disease.

Thylacine; Thylacinus cynocephalus
Extinct.

Wedge Tailed Eagle; Aquila audax
Found in many different habitats. Almost black when mature. Has feathered legs and a long wedge shaped tail. Very big - wingspan up to 2.2m and can weigh up to 5kg. Tasmanian subspecies has been isolated from the mainland since the last ice age 10,000 years ago. There are only 130 successful breedings each year, so they are listed as endangered. Major threats are habitat loss, nest disturbance, collisions with power lines etc. and illegal shooting etc.

Yellow Wattle Bird; Anthochaera paradoxa
World's largest honey eater.

Forty spotted pardalote Pardalotus quadragintus
One of the smallest birds in Australia, about 9 to 10 cm. Also one of the rarest and threatened with extinction. Only live in Eucalyptus viminalis forests (white gum). Feed on insect, lerp (insect coating), manna (plant secretion in response to insect attack). They are called foliage gleaners because of the way they pick insects from leaves and branches.

Tiger Snake; Notechis scutatus

Blotched Blue Tongue Lizard; Tiliqua nigrolutea

Spotted Handfish; Brachionichths hirstutus
Critically Endangered. Marine fish. Only found in sandy sediments around Derwent Estuary and surrounding bays (ie. where I live ). They walk slowly along the seafloor using their pelvic and pectoral fins, which look like hands. They are endangered because of the invasion of the introduced seastar Asterias amurensis into their habits and because changed land usage has increased run off, damaging their habitats. They have also been making global news recently, featured on many blogs I read, because a bunch of new species have been discovered. Here is one of the stories with photos

http://news.nationalgeographic.com/news ... -pictures/

Giant Freshwater Crayfish; Astacopsis gouldii
Is the world's largest freshwater invertebrate. Ranges in colour from dark navy blue to bright blue. Omnivorous and found in streams and rivers in the north and north west of Tasmania. Feeds on rotting wood, animal flesh, leaves and insects.

Giant Velvet Worm Tasmanipatus barrettii
Can grow up to 7.5cm big.

Tasmanian Echidna; Tachyglossus aculeatus setosus
The unit co-ordinator, assoc. prof. Stewart Nicol specialises in these

Why are these animals in Tasmania? Where are they found in Tasmania?

What processes, past and present, have determined the make-up and distribution of the Tasmanian fauna?

Tasmania is the coolest, wettest part of the continent of Australia. It's the most isolated part of an isolated continent. It is very diverse compared with a more homogenous mainland. The fauna has high levels of endemics, a lot of evolutionary relics, unusual radiations and also island poverty (unfilled niches, etc.)

Tasmanian Physical Geography
Tasmania is 67,800 km ^2. About the same size as Ireland, slightly smaller than Hokkaido and slightly larger than South Carolina. Found at 42-43 degrees South. About the same distance from the equator as Boston, Madrid and Sapporo. Population 500,000. Climate in Tasmania is temperate and similar to south east and south west mainland coast. Rainfall is divided across the state. West coast has very high rainfall, and there is a patch of high rainfall on the North East. East is generally much drier. Hobart has the second lowest rainfall of any capital city in Australia. Weather is dominated by prevailing westerlies (roaring 40s) and mid latitude highs that drift down over summer. Long mountain range running down middle of state is responsible for rain variation - East side is in its rain shadow. Geology consists of Jurassic dolerite intruding in to permian and triassic mudstone in the east and south east. Quartzite soils in the south west. Cambrian volcanoes in the west and granite in the north east. Vegetation somewhat reflects geology. Made up of rainforest, wet eucalyptus forest and woodland, highland treeless, native grasslands, wetlands and saltmarshes, moorland, peatland and sedgelands, scrub, heathland and coastal, marine, and agricultural. Vegetation reflects both climate and geology, but climate has the biggest impact. Fire also plays a role, and produces disclimaxes.

These kinds of physical factors play a big role in predicting animal distribution but biological and historical factors are also important. Tyler's Line is an imaginary line running down the west that shows a significant difference in distribution either side of the line - consistent with geology and rainfall leading to different vegetation. Examples of animals restricted by that line include some grasshoppers, crayfish, and land hoppers.

*Focus Question*
Many components of Tasmania fauna show a distinct difference between the west and east. What are the main factors responsible for this?

Tasmania is broken down in to 9 bioregions;
West, Central Highlands, Southern Ranges, Ben Lomond, South East, Northern Slopes, Flinders, and King.

[Jeremy]

Lecture 2
What process, past and present, have determined the make up and distribution of the Tasmanian fauna?

Dispersal Tree; Dispersal>behaviour>other species>physical or chemical factors.

So can it actually get there? Does it choose to evade their for some reason? Does it face predators, parasites, competition or disease in that area? Are the conditions suitable for it to actually be able to live.


Tasmania has been isolated from the mainland for 10,000 years, was part of Gondwana and before that Pangaea. Fauna on Tasmania represents all these links;

Pangaean fauna includes things like velvet worms, cockroaches, freshwater amphipods and velvet worms.

Gondwanan fauna can be divided into early and late fauna. Early is things like landhoppers and amphipods. Late is things like marsupials and ratites. Ratites are large flightless birds like emus, and are now extinct on Tasmania, but there are fossil and historical records.

Other animals have got here via migration because of our close proximity to Asia. They include dragonflies and some birds such as beautiful firetails and welcome swallows.

Then there are recent arrivals which can be split between human introductions and natural introductions. Human introductions include rats, mice, blackbirds, honey bees, European wasps, foxes and many more. Natural arrivals include kelp gulls and cattle egrets.

Gondwana in the late Jurassic connected Australia (and Tasmania) to Antarctica, South America, Africa, India and Madagascar. By 50mya these were all separated into the continents we see today. By about 14mya they were largely in the positions we see today.

250 million years ago Gondwana began to break up. At this point Australia was near the south pole and had a cool temperate climate. Monotremes separated around this point. 200mya the climate was warm and humid. It was about this time that the first birds appeared in Europe. 140 mya the conditions in South Australia (if not all) were polar. 65mya an asteroid collided with the Earth wiping out the dinosaurs and opening up the Tasman sea - the gap between Australia and NZ. The oldest marsupials, bats and songbirds all come from this time. Australia separated from Antarctica fully by 55mya and Gondwanan fauna was no longer able to migrate by land by 50mya. 34mya migration to Australia from Asia began. Australia had a fairly wet climate. 24mya was a major greenhouse event and warm temperatures. 16.4mya was a major ice age. 11.2mya Australia had a dry seasonal climate. 5.3mya Australia developed its first arid habitats, the first grazing mammals and Australian rodents appeared and there was a small greenhouse event. Humans arrived 43kya and there was a mass extinction wiping out most megafauna 40kya. There were many glacial periods in this time. The last one finished 10kya and since then things have been warmish and wet. Europeans arrived in the 17th C.

In recent geological history the Milankovitch cycles of glacial and interglacial periods have had an impact on sea level. Tasmania is a continental island that is periodically connected to the mainland when sea levels are lower. There have been 4 major glaciations in the last 800kya. Due to rain shadow, at the last glaciation the snow line was much lower on the west coast than the east, although periglacial effects were at the same level across the island. Ice began to retreat from the last glaciation about 18kya. By 10kya Bass Strait began to flood, cutting of Tasmania from the mainland. Climate became wetter and milder, resulting in the spread of Nothofagus. About 8-5kya Eucalyptus started spreading and took over as the most dominate tree. Present vegetation has remained the same for the last 6kya. El-nino cycles have been present for the last 5kya.

Rainfall cycles have led to periods of aridity and drought.

Bass Strait was entirely land, but mainly low lying marshes during the last glacial period. As sea levels began to rise an estuarine environment appeared in the middle of the area as water flowed in from the north west. Eventually it filled with water, with the last connection being on the Flinders Island side.

Predictions of fauna based on current conditions are that species would be adapted to cool wet conditions and have a competitive advantage. Presence of species that have evolved in habitats not found on the mainland. Fewer species than on a similar area of land on the mainland.

Predictions from historical events are ancient groups that have not been subject to competition, Gondwanan elements, recent colonisers from the north.

Predictions within Tasmania are for an east/west gradations in distribution. Echoes of Pleistocene glaciation.

*Focus Question*
List 2 major geological events that have been important in shaping Tasmanian fauna. When did they occur? What were their effects?"

Endemism
Requires sufficient isolation for evolutionary differentiation to take place. Distribution needs to be restricted to a certain place - ie. Tasmania. Depends on time since isolation and the degree of isolation. The effect of these in turn depends on the vagility of the species - how well they move and disperse through their environment.

Example; double invasion of thornbills. Early invasion by brown thornbill. Tasmanian then cut off from mainland. This population evolved in to Tasmanian Thornbills. Brown thornbills then re-invaded, meaning both species are present.

In Tasmania species with high vagility have low rates of endemism, while species with low vagility have very high rates of endemism. Fresh water based invertebrates have especially high rates of endemism.

Tasmania has a limited bird fauna compared with the mainland, with lower species density. However many species are either endemic or have endemic subspecies. This goes for other animals too, such as wombats, possums etc.

[Jeremy]

Lecture 3
Marine habitats of Tasmania

Lecture by Dr. Scott Ling.

Importance of scale looking at marine environments - impacted by things from global scale such as climate etc. down to very local scale such as tide lines etc.

Humans have many interactions with the coast; commercial fishing; recreational activities, pollution, coastal development, tourism, climate change etc.

Consequence of interactions can include things like stock collapse, species collapse, range changes, exotic species introduction, regime shifts, habitat fragmentation, loss of top predators, major change in community composition, trophic collapses.

Tasmania has 8 marine bioregions. Otway, Central Bass Straight, Flinders, Boags (also the name of one of our main beer breweries ), Freycinet, Bruny, Davey, and Franklin. The first four are in the Northern Province and the second four are the Southern Province. The regions are based on plant and animals found in each region. There are some marine protected areas around here too, of varying levels of protection.

Marine life can either swim or be swept. Swimmers tend to be pelagic, such as sharks, tuna etc. Sweepers are smaller such as invertebrate larvae. Often the adult is benthic (on the sea floor) while the larvae are pelagic. However many swimmers swim following ocean currents while many sweepers appear to still have control over where they end up, so the distinction between the two is not black and white.

Major Currents;
East Australia Current. Runs down the east coast bring warm water. Has been moving much further south in recent years. Has an impact on the Freycinet bioregion and many NSW vagrants are now found there. Could be what we should expect with climate change. Waters around Tasmania have risen significantly over the last few years. The EAC has also moved 350km further south in the last 50 years. This has resulted in many fish extending their ranges further south and in to Tasmanian waters, which is putting pressure on local species, especially those that can't move further south.

The long-spined sea urchin Centrostephanus rodgersii is an example of a species extending its range in to Tasmania and having a big impact. It needs water over 12 degrees in winter to become established. In recent years that has been happening, so it's become established and is destroying kelp forests.

The acorn barnacle Austromegabalanus nigrescens is another species to be recently established on exposed eastern shores in the last few decades, probably due to warming as well.

On the west side currents come from the roaring 40s and the Leeuwin current.

The west coast is much more exposed than the east coast with swell sometimes bigger than 10m...

Tasmania's coastline is exposed to many different conditions and is made up of soft sediments such as beaches and rocky reef habitats. Rocky reefs dominate the coastal fringe and support a high level of biodiversity but variation in topography and exposure make big differences to the biota of rocky reefs.

Sunlit rocky reefs in temperate regions are dominated by seaweed and support commercially valuable industries such as the rock lobster and abalone industries. Sheltered and exposed sunlit rocky reefs have very different types of seaweed. The exposed East Coast reefs typically have Phyllospora (a common brown macroalgae) forests around the water line, Ecklonia (common kelp) forest deeper and a sponge "garden" at the deepest edge. There are a range of fish found, which tend to inhabit certain depths, and many different invertebrates.

Rocky shores.
On rocky shores the amount of exposure tends to determine the species. More exposed means more mobile species. Less exposed means more sessile and less mobile species. Zonation in Tasmania is not as strongly marked and obvious as in higher latitudes. Mussels don't form extensive beds and brown algae is much less extensive in intertidal zones. Typically upper limits are set by physical tolerance while lower limits are set by predation and competition. Mussels in Tasmania are prominent but not band forming. Probably controlled by predators such as the seastar Patiriella calcar which feeds at high tide and then returns to crevices and pools at low tide. They are slow moving so their range is limited. There are mussel free zones at the edges of crevices, supporting this theory. Whelks are barnacle predators that are similar and there are also barnacle free zones around crevices, presumably for the same reasons.

Summary;

There are links between open ocean and what we find on the coastline. Large scale physical processes influence what we find at particular stretches of coast. Smaller scale processes also influence what we find, ie. local physical processes and biological interactions.

[Jeremy]

Lecture 4

Dr. Scott Ling

Species interactions

In Tasmania many kelp forests have been disappearing, especially on the East Coast. Dr. Ling has been studying this. The reason for the disappearance appears to be the sea urchins. When sea urchins reach large numbers they destroy the kelp and don't let it grow back. This is an example of extreme herbivory. The sea urchins are becoming a problem in Tasmania due to warming waters and the extension of the EAC. They do have predators, but their predators are being consumed by Humans - especially rock lobsters, so that's increasing their numbers.

Ecosystems can be viewed as top down or bottom up - referring to the trophic level. Ie. either the top predators control the populations of their prey, or the lowest trophic level biota control the populations of the predators. Top down seems to be more accurate for local populations, while bottom up gives a better bigger scale picture. However in most cases it's not either/or but a mix of both influencing each other.

Kelp barrens caused by sea urchins represent a catastrophic shift where destroying the kelp makes conditions better for the sea urchins and worse for the kelp so that it's very hard for the kelp to re-establish and a completely different ecosystem comes to exist. When barrens form about 150 different taxa are lost. Urchin barrens and kelp beds represent two different stable states for the ecosystem and it's hard to move between them. Species that drive these shifts are called "ecosystem engineers" because such species can determine habitat and impact on an entire ecosystem. Such barrens could represent 50% of Tasmanian east coast rocky reefs if they're not addressed.

However the urchins main predator is the rock lobster. In areas of the right climatic conditions for urchins where taking rock lobster is banned, the amount of rock lobster is much bigger, their sizes are much bigger and there are no barrens. The urchins in such areas are much smaller and most don't reach maturity. Studies show that lobsters are only capable of eating adult urchins when they get to around the size of the legal limit - so the ones that people are taking are the ones that would solve the problem.

Summary;

Grazing of Centrostephanus can cause catastrophic ecosystem shifts from macroalgae to sea urchin barrens.

The Eastern Tasmanian climate is warming and becoming more favourable to Centrostephanus which is increasing the risk of further sea urchin barrens.

Overfishing predators reduces the resilience of the macroalgae beds against climate change which makes catastrophic shifts.

Maintaining and restoring healthy ecosystems to increase resilience is the best hope for ecosystems to deal with a warming and uncertain future.

[Jeremy]

Taking a break from lectures to answer a series of past exam questions that I couldn't answer off the top of my head;

These aren't the actual answer I'd write for the question, just a summary of information we've been given relating to it. The exam is made up of something like 12 questions, of which you have to answer 6, taking 15 or 20 minutes per question - so about a written page per question.

1. Why are frogs particularly sensitive to environmental disturbance?

Frogs require both aquatic and terrestrial habitats, which makes conservation hard. They are also very vulnerable because they go through metamorphosis. This period is when they are most vulnerable because they need suitable refuge and have a high surface area. When they're metamorphosing they are less capable as tadpoles and as frogs - they can't move as well etc.

The threats facing frogs are;

Habitat loss and modification - structure of pond margins, patterns of stream flow, water quality and drainage.
Introduction of fish
Loss of native vegetation and litter cover
Grazing by stock
pesticide and herbicide use
UV and global warming
Chytrid fungus

Amphibians are under threat globally. 1 in 3 known species are listed as endangered. Almost 50% of known species are declining in population size. As many as 165 species have gone extinct in recent years. A greater proportion are at risk of extinction than any other class of animal.

Repeating major threats; Habitat Destruction, Pollution, Climate Change, UV Radiation, Predators and Disease.


Read more RE bats for writing short notes on a mammal that lives in tree hollows. The question was to name 4 species of animal that live in tree hollows with short notes about two of them. It asked for only 1 mammal at the most, which is good because I can easily name 4 birds

There are 8 known species of bat in Tasmania. They are all microbats in the family Vespertilionidae. Vespertilionidae make up a third of all bats, and 50% of Australian bats. Tasmania is a Vespertilionidae hot spot! They are broken up in to two subfamiles - Nyctophilinae, which are long eared bats, of which there are 2 species in Tas and Vespertilioninae - which are evening bats and forest bats.

Species as follows
Tasmanian Long-eared Bat
Nyctophilus sherrini
Very recently declared a separate species - used to be considered N. timoriensis. Tasmania's only endemic bat species. Large - forearm about 45mm. Females are 11-15g. Males 14-21g. Roosts in tree hollows, fissures in branches and under bark. Habitat is blackwood swamps, dense tea tree, coastal mallee, wet sclerophyll forests - ie. thick vegetated and wet habitats. Eats non-flying insects such as caterpillars, scorpions and moths (when not flying). Also sometimes known to forage on the ground. It is an example of Neoendemism.

Lesser Long-eared Bat
Nyctophilus geoffroyi
Wide spread. Subspecies N. g. pacificus is Tassie species and southern mainland. 3 subspecies in total. Roosts in dead trees, either in hollows or under bark. Also sometimes in buildings. Forms small colonies. Smaller than Tassie leb. Forearm 30 to 40mm, 6-12g. Forages flying very slowly and highly manoeuvrable. Diet is moths, crickets, grasshoppers, flightless insects, and more. Uses echolocation to catch prey in the air, on foliage or on the ground. Also passive listening for ground and aerial prey and also vision for aerial prey.

Gould's wattle bat
Chalinolobus gouldii
Found everywhere. Roosts in tree hollows. Males are usually solitary, females form hot lesbian colonies. Hot lesbian part might not be true. Eat mainly bugs and moths. Fast and high flyer. Often emerges just after sunset when there is still a lot of ambient light and is vulnerable to predation from owls, falcons, butcherbirds, currawongs and feral cats.

Chocolate wattle bat
Chalinolobus morio
Common over a wide range of habitats. Roosts in tree hollows. Is an opportunistic forager and is the last Tassie bat to enter hibernation for the winter and the first bat to be seen in spring.

Eastern False Pipistrelle
Falsistrellus tasmaniensis
Large, robust bat - 17-28g.
Found in all habitats and eats moths and beetles. Usually targets the largest available prey.

Southern Forest Bat
Vespadelus regulus
Common and small - 3.6-7g. Wide range of habitats. Males roost singly, females form colonies of up to 100 individuals. Aerial insectivore - favours moths.

Little Forest Bat
Vespadelus vulturnus
One of Australia's smallest mammals - about 2.5 to 5.5g. Common. Feeds on flying insects, usually below the tree line. Uses tree hollows.

Large Forest Bat
Vespadelus darlingtoni
Common. Distinctive long fur, large size. Forearm 35mm. Weighs 4-10g. Less manoeuvrable than most Vespadelus

Summary.

8 bat species, 1 endemic. Important for controlling insect numbers. Transfer nutrients in to forests. Use tree hollows. Hibernate in winter. Store eggs and sperm over winter until end of hibernation. Young are born in October - February.

[Jeremy]

Lecture 5

Marine mammals and seabirds 1

Dr K. Wheatley

Rushing through this because I know it well

Marine birds and mammals face big challenges due to living in air and water. They can't exchange gases at all times, they have increased heat loss, they have differences in density of mediums, greater resistance to movement in water, changes in sound propagation and low light conditions. The degree of adaptation depends on how long they tend to spend in the water. All of these challenges ultimately are caused by the density issue. Because birds and mammals don't have gills, they need to breathe air, so are "divers" rather than swimmers.

However the marine environment has much larger abundance of food than the terrestrial environment. They can be divided in to "land breeders" - seals and seabirds, and "sea breaders" - cetaceans (and dugongs).

Adaptations to the environment are; Streamlining - loss and reduction of limbs and ears as well as more streamline shape. Thermoregulation changes - especially thick fur, pelt, modified feathers with down, or layer of blubber. Modified locomotion - flippers, flukes or webbed feat. Dive response - Bradycardia (slowed heart beat), highly developed ability to hold breath. Vaso-constriction and regulated blood flow (less blood flow to limbs, outer surface etc.) Reduction in body temp and metabolic rate.

Oceans are not homogenous - have structure, currents etc. Two major currents - East Australia Current down east coast of Aus/Tas. Brings warm water. Warmer water is less nutritional so brings less food and so smaller marine mammal and bird life as a result. West Coast current is Zeehan current.

Two types of Cetaceans - Mysticete - filter feeders and Odontocete - toothed.

Mysticetes - baleen whales, southern right whales (used to be hunted in Derwent - ie. in the bay Hobart is built around. Hunted almost to extinction), Humpback whale - breeds around tropics, feeds in polar regions - migrates past Tas from one to other.

Odontocetes

Dolphins
2 main types - bottle nosed and common. Bottle nosed is more common than common.

Also southern right whale dolphin - named after southern right whale because neither have a dorsal fin. Rare visitor to Tas waters.

Pilot whales. Sperm Whale.

Cetacean strandings in Tas.

Tasmania has more strandings than anywhere else in Tas. Typically pilot whales, sperm whales and common dolphins. Up to 32 strandings a year, between 1 and 120 individuals.

Lecture 6

Strandings seem to occur along a quasi-decadal cycle. The cycle coincides with large scale cycles in weather, especially Zonal West winds - a continental trough that moves latitudinal over a 10-14 year cycle.


Land breeders.

Seals are divided in to two types - true seals, and fur seals and sea lions. Fur seals and sea lions have visible ears, are polygynous and have a relatively long lactation period. True seals have no visible ears, hind flippers can't be turned under them but are used for locomotion, various mating systems, shorter lactation periods and are just occasional visitors to Tassie.

Examples of true seals are;

Southern Elephant Seal - forms big colonies, big difference between male and females, very polygynous. Leopard seal.

Eared seals and sea lions are found around tas. Aussie fur seals bread on rocky outcrops around Tassie waters. Have issues with commercial fishing - with fish farms and problem of either not having enough food due to fishing, or taking fish meaning fishing less profitable.

Seabirds - At least 45 found in Tas, of which 16 breed here.

Short Tailed Shearwaters - breed in southern Aus waters, then fly to Bering sea for our winter. Also fly past South America on their way here. Still hunted and eaten by indigenous australians. In my opinion taste terrible - basically a bird made out of fish oil.

Shy Albatross.

Other birds.

Macquarie Island is a Tassie territory but a subantarctic island. Low species diversity but high abundance. Problems with feral species such as rabbits and political nightmare.

[Jeremy]

Lecture 7

Birds 1

M. Todd.

Smashing through these because they are my strongest topic

Approx. 230 species have been identified in Tas. 126 breed here. There are also a handful of introduced that breed - sparrow, goldfinch etc. The others are migratory birds that come here for summer and typically breed in NH in our winter. Availability of bird habitats is big predictor of species dispersal. There is big variation of species between habitats.

Habitats;

Fresh and saltwater wetlands. No endemics.

Beaches. Limited in size but Tassie has a lot. No endemics.

Heath and sedgelands - usually occur on poor soils, particularly in the west. No endemics.

Rainforest - low bird diversity and abundance. Scrubtit found (endemic). Dominated by Nothofagus trees - Gondwanan link.

Eucalypt Forest and woodlands - provide greatest bird habitats. Natural habitat for most endemic species. Range from open dry to tall wet.

Agriculture and pastoral. Typically most fertile land that has been cleared. Provides new habitat for some species.

Urban - mainly provides habitat for introduced species

Flight - feathers are specialised. Forelimbs evolved for flight (wings). Hollow bones.

Migration - many Tassie birds migrate. Usually from areas of scarce food to higher food - usually due to changing seasons. Occurs at different scales.

Intercontinental. Typically seabirds and waders. 66% of waders in Australia spend our winters in the Northern Hemisphere.

Latham's Snipe - breeds in Japan/Manchuria area. Non breeding found all along Aussie east coast. Eastern Curlew - similar, but also found across North coast of Aus. Sharp-tailed Sandpiper - breeds in arctic circle, spends summer all along Aussie coast. Bar-tailed Godwit similar.

Intracontinental migration - Often breed in Tas and then fly to mainland for their winter. Cuckoos. Parrots - Swift and Orange - both are breeding endemics to Tas (only breed in Tas) and both are endangered. Orange critically - less than 40 birds remain and the latest environmental advice is to capture all birds to be just be bred in captivity - ie. will soon be extinct in the wild. Silvereye.

Altitudinal migration. Nest at high altitudes in summer but then move towards coast in winter. Example - Flame Robin.

There are 12 endemic birds in Tas. Also many endemic subspecies. Passerines - perching birds.

Climate change
Tassie avifauna shaped by historic climate change. Rising and falling sea levels and glaciations. During glaciers tree line much lower. Reduced distribution of woodlands etc. that have highest bird diversity.

Separation from mainland also factor - many endemic species evolved since we've been separated -

Larger islands have more habitat diversity so more bird diversity. Bass Strait is obvious barrier to dispersal, although birds can be blown across it. Dry birds vs wet birds. Extensive areas of unfavourable habitat can also be barrier. There is much greater diversity on East Tas than the "old" wetter forest on West Tas.

Tas has less diversity than mainland, but on a very local level, is comparable. This means that overall there is more species in common from place to place in Tas than on mainland. Similar things are seen with islands in North America. This could mean that Tassie habitats are "saturated" with bird species - no room for more species. Supporting this theory, mainland birds often make journey across Bass strait but are unable to establish themselves. Human activities changing habitats could help them establish. They have trouble establishing due to competition from natives. Also the shorter winters could be a factor.


Bergmann's Rule
With a species the body mass increases with latitude and colder climates. Applied usually to endotherms but has been shown in some ectotherms. Eg. Tassie birds should be larger than relatives on mainland. Main reasons are that larger animals maintain heat better and can survive food shortages of colder climates better.

Gloger's Rule
Within a species or subspecies the more heavily pigmented forms tend to be found in more humid environments. Tassie is more humid than mainland so should be more pigmented. Two reasons for this. 1. Dark feathers absorb heat while lighter feathers reflect it. So having lighter feathers in hot dry conditions means saves water, keeps cool and can feed for longer. Likewise having darker feathers in cool wet conditions means keeping heat better.

Also darker feathers are more resilient to feather damaging bacteria. Feather damaging bacteria is more common in wet conditions so more advantageous.

[Jeremy]

Lecture 8

Birds2
M. Todd.

Tassie Birds. Missing in our fauna - bark foraging birds. Many species on mainland, none in Tas.

13 endemics as follows;

King Island Emu - extinct
Tassie Native Hen
Green Rosella - largest rosella.
Dusky Robin
Tassie Thornbill
Scrubtit
Tassie Scrubwren
Yellow Wattlebird - world's largest honey eater
Yellow throated honey eater
Black-headed honey eater
Strong-billed honey eater
Black Currawong
Forty-spotted pardalote - endangered

Breeding endemics;

Orange Bellied Parrot
Swift Parrot
Both critically endangered.

[Jeremy]

Lecture 9 Freshwater

Dr. C Burridge

Tassie current freshwater environment;

Lots of lakes and rivers.

Diversity of habitat types caused by rainfall gradients, flow regimes, temperatures (snow melt, low land). Distinct water chemistries (Tyler's Line) - electrolytes, pH.

Tyler's line - Differentiating big rainfall gradient across Tassie. Dominated by roaring 40s etc. On west coast precipitation is greater than evaporation. Opposite on east side.

Geology either side of Tyler's line also different - granite and Jurassic dolerite intruded into permian and Triassic sand and mudstone on east side. Cambrian volcanics on west side and quartzite on south west side. All are old rocks and tectonically stable.

Rotifers - small pseudocoelomates. Mostly freshwater, found all around the world. There are 13 endemic species of rotifers in Tassie. 11 are found on West Side. Acidophilic - water is dark, humic, acidic and low in electrolytes. 2 species on east side where water is less humic, some alkaline and higher in alkaline.

Many other species reflect tyler's line such as frogs; Litoria burrowsi vs L. raniformis, crayfish - Astacopsis franklinii vs A. tricornis, landhoppers, grasshoppers etc. There are many species that don't conform to Tyler's Line.

Tassie has a long history of freshwater environments. Has never been particularly arid although has been getting slowly drier now. Long stable geology with hard bedrock, slow erosion and so old catchments.

During glacial climatic periods some higher altitudes are uninhabitable but new habitats are also created (such as tarns etc.) and at these times there are freshwater connections to the mainland - Bassian plane etc. During the Pleistocene glacial periods are the norm, not rare. During glacial periods larger areas of Tassie FW are inhabited due to either presence of glaciers or severe periglacial effects - ie. too much freezing and thawing. 4 major glaciations in Pleistocene. Current distributions of freshwater biota may reflect impact of these.

Bass lake present during glaciations because sea levels are higher - fresh water connection to mainland.

*Focus question* - Describe three environmental factors that may influence the distribution of FW taxa and describe how they vary through space and/or time.

Tassie FW Taxa

Invertebrates - rotifers, crustaceans, molluscs, insects etc.

Vertebrates - Agnathans and bony fish, amphibians, birds and mammals.

Missing reptiles (crocodiles, turtles etc.)

Tassie FW fish
25 species including Agnathans. Includes taxa that are only FW for part of life cycle (diadromous). Excludes marine vagrants and estuarine taxa. Fish as follows; Agnathans 2 species. Anguilid eels - 2 species. Galaxids 2 spec. Retropinned smelt 1 spp. Percichthyids 2spp. Notothenioid 1 spp.

Umack (2000) defined Tassie in two provinces - Northern Tas and Southern Tas. Do not share any taxa.

Islands have low biodiversity by high endemicism. Australia has declining diversity with latitude.

[Jeremy]

Lecture 10

Freshwater 2

Dispersal of fish is very dependent on whether they are diadromous, not, or can be both. Diadromous means that live in fresh and salt water. Diadromous have much bigger dispersal and around coast. Non are very restricted and have very high rates of endemicism. Both have big dispersal ranges but also the possibility of specifying in to one of each - especially when they get trapped in only fresh water environments.

Origin of FW taxa

Pangea - should be then found around the world in manner that can't be explained by distribution abilities.

Gondwana - found only on Gondwanan continents.

Examples - Galaxids. Could be by dispersal though. Controversy!



Gondwana - found in only

[Jeremy]

Lecture 11.

Freshwater 3

Origins of FW taxa

Bassian Plain (ie. before end of last glacial period. Should be taxa shared with Bass Islands, Southern mainland and North Tas (but not south Tas).

Marine invaders;

Either adapting to fresh water conditions, FW taxa with a marine life history stage, or rafting.

There can also be aerial invaders - FW taxa with areal life history stage - ie. some insects.

Diadromous species can lose their marine life cycle and become FW only - especially if landlocked such as some galaxids. Can be in either laval stage or adult stage - eg. some eels are marine as adults but FW as juveniles.

No evidence that rafting of species in Tas.

Kelp gull is an example of an aerial invader.

Conservation issues with FW taxa.
Threats - introduced species. Water quality (including pollution). Water quantity.

[Jeremy]

Lecture 12

Cryptozoa

P. McQuillan

Invertebrates - typically 0.01mm to 100mm in size. Very diverse. Typically have poor control over water loss and rely on humid conditions of their environment to maintain water balance.

Velvet worms - very ancient, haven't changed in 530 million years.

Tassie hairy cicada is a relic from the mesozoic. A proto-cicada. Can't sing but can communicate in ultra sound by vibrating their bodies. Immature stages live in soil and eat roots.

Simpson's Stag Beetle. NE Tas is a stag beetle hot spot!

Pangaean distribution - Cupedidae - longihorn beetles.

Cryptozoan habitats are buffered from the wider environment - micro climates etc. and can persist for millennia. Cool, wet, shaded with no wind. Lots of interstitial spaces (tiny crevices etc.)

Habitats such as soil, ground litter, decaying logs, moss beds, fungi, beneath bark of eucalyptus, perched litter in tree crowns, tree canopies, caves, ants nests etc.

Communities may change as environment changes, ie. as at different stages of the decay of a log there are different communities.

Ecosystem engineers - change habitats to their advantage etc.

Channelizers of wood - ie. beetle larvae.
Aerators of soil - earthworms, ants, termites.
Comminters of litter (pulverise it) - moth larvae, beetle larvae
Flammability reducers - by reducing fuel keeps forest less fire prone.

Cryptozoan predators often have mouth parts adapted for specific prey.

Ants!
Australia has over 1000 species of ants that are involved in many key ecological functions. Seed dispersal. Predation - both specific and generalist. Soil mixing. Prey for lizards, birds and echidnas. Symbiosis with butterfly larvae, sap suckers etc. Tassie has about 120 species of ants, mainly found in the East.

Rove beetles - small, linear beetles adapted to live in leaf litter and interstitial spaces. More than 200 species in Tas.

Wolf and trapdoor spiders can persist in small habitat patches if prey is diverse and abundant. Orb web spiders disappear from cleared land as the habitat becomes 2 dimensional.

Insect larvae are major detritivores in forest litter. They also recycle nutrients, maintain selection pressure on plants and serve as food for birds etc.

Mites - several hundred species of mite in Tas. Assist in nutrient recycling in leaf litter and humus.

Species can vary in responses to habitat loss and fragmentation - can increase or decrease in populations. Boom/bust species. Body size can be important as smaller means their home range is smaller etc. Species at higher trophic levels are more sensitive.

Increasers - increase in population because the change in habitat either benefits them or disadvantages their competitors and predators.

Decreasers - Especially pollinators, parasites, fungus feeders, litter feeders and moss feeders.

In a fragmentation experiment scorpions remained at similar levels while amphipods decreased dramatically. Probably caused by changes to microclimate.

Movement of ground dwelling beetles in fragmented habitats is controlled by the shape of their patch, the boundary contrast between the patch and the overall matrix. Gradual boundaries are more permeable for ground beetles than hard boundaries.

Predators of cryptozoa
Birds with raking feet - Lyrebirds, Mallee fowl, Bush Turkey, Bassian thrush.
Mammals such as Echidna, antichinus, barred bandicoot.
Reptiles - skinks and legless lizards
Invertebrates such as snails.

[Jeremy]

Lecture 13-14

Caves
Dr N Doran

Types of caves; Sea caves, Lava tubes, Karst, pseudo-caves.

Sea caves are formed by wave action against rock etc. Usually in very high energy environments. Usually develop at weaknesses in rocks (faults etc.) or intrusions in rock by weaker rocks etc.

Lava tubes - formed by lava cooling on top and remaining warm in middle etc. Can be very long. Not found in Tas.

Pseudo-caves. Formed by rock falls etc.

Karst - Formed in water soluble rocks, especially limestone. When the limestone is deposited it forms many cave decorations called speleothems such as stalactites etc. Caves also often feature decorations and human artefacts from prehistory etc.

In Tassie there are lots of caves - 140 cave areas with 2770 documented caves and probably over 4000 in total. 95% of which are karst caves.

In contrast to the outside environment that can often be lusher and more fertile than surrounds, cave environments often appear to be barren of life. However there is actually diverse life in caves if you know where to look. It is typically small, cryptic, sparse, and hidden in nooks and crannies.

Caves are defined by their ability to allow human movement, but cave fauna can inhabit places that humans can't and be found in mesocavernous voids and interstitial flows etc.

Environment of caves makes spotting fauna very difficult - low light etc.

Key aquatic groups of cave fauna; hydrobiid snails, crangonyctoid amphipods, syncarid shrimps, isopods, and flat worms.

Astacopsis gouldi - giant freshwater crayfish found in Gunns Plains caves.

Key terrestrial groups; Spiders, harvestmen, mites, pseudoscorpions, beetles, crickets, springtails, isopods, millipedes, oligochaete worms, and land snails.

Cave zones

1. Entrance zone or mouth. Surface and underground conditions meet. Conditions very variable. There is deflected light here and growth due to that. Things like stalactites can "grow" towards light due to impact of photosynthetic bacteria etc.

2. Twilight Zone - light diminishes but temperature remains variable. Gay vampires found here.

3. Transition or middle zone. Complete darkness but still under the impact of outside environmental influences through streams and or air currents.

4. Deep cave or Dark Zone. Also known as troglic region. A long way from entrance. Temperature stable and high humidity. Very little evaporation.


Cave conditions; There is no light in caves so there is minimal autotrophic production which makes them nutrient poor. Biomass is low but diversity is high. The major food inputs are from trogloxenes - prey, droppings, eggs. Streams. Entrance infall. Root ingrowth.

High humidity - relative humidity 95-100%. Temperature is average and constant. CO2 can be very high, up to 10%+, particularly in tropical areas (compared with 0.04% in normal atmosphere). Highly predictable environments.

Cave animals - in ecological groupings instead of taxonomic groupings.

Troglobites;
Obligate cave species. Adapted to cave environments and can't live outside of them. Predominately found in deep cave environments. Many morphological, physiological and behavioural adaptations - can be quite bizarre.

"troglomorphisms" - loss or reduction of eyes. Loss of pigmentation. Elongated limbs. Giantism and dwarfism. Strong thigmotactic behaviour - innate response to touch etc. Hyper development of tactile, gustatory, olfactory, and auditory organs - ie. all senses other than sight. Ability to cope with high humidity and CO2 tolerance. High sensitivity to changes in humidity and CO2 levels. Low metabolic rates and high resistance to starvation. Increased longevity with slower development, growth and maturation. Reduced seasonality and diurnal behaviour. Stimulation of breeding by non light cues such as seasonal flooding. Exceptional resistance to fungal infections.

Troglophiles
Facultative cavernicoles. Commonly live and reproduce in caves but not confined to them. Can be found in similar sheltered, cool, dark and humid surface habitats.

Trogloxenes
Occasional cave animals. Regularly inhabit caves for refuge and microclimate but must return to surface to feed - usually at night. Usually inhabit entrance. Example - bats, but not in Tasmania. Cave crickets are a common example in Tassie.

Accidentals
Animals that fall, wander or are washed into the cave environment but cannot survive there - must leave or die. Vertebrates are rare but sometimes occur - fish, wombats etc.

The importance of caves, karst and associated fauna range from academic and scientific to economic and practical values. Cave species tend to be of high evolutionary importance both as relictual species and as highly adapted species. Cave species tend to have high biogeographic importance. Caves tend to have simple systems that can be used to test scientific theories of more complicated ecosystems. Have potentially high public and cultural value (tourism, spelunking, archaeology etc. ). Have potential for industrial use - funguscides etc. Are sensitive indicators of ground water health. Can be used as a yardstick - are sensitive and discrete that may demonstrate the effectiveness of broader management strategies.

Epigean (above ground) flora - regrowth on karsts is not good - erosion, slower regrowth etc. so good not to clear vegetation on karst areas.

Caves and cave fauna are increasingly subject to pressure from the flow down effects of surface habitat degradation. Activities effecting soil, vegetation, atmospheric conditions and water catchments can impact on cave systems. Key management issues include; agriculture, forestry, limestone quarries, pollution and waste management, tourism, scientific research. Caves are sensitive to the outside environment because they are not isolated on it but actually depend upon it.

Clearing of outside of environment can impact on food coming into the cave - systems, roots, trogloxenes, and number of accidentals. Changes in stream levels can alter humidity, temperature, and reproductive cues within the cave. Changes to the outside atmosphere can result in changes of cave humidity and air flow and result in changes of cave zones. Pollution can poison groundwater, take longer to break down, also physical pollution can be a problem, such as increases in silt.

Disturbance may allow new competitors to compete with current cave taxa, or unbalance ecosystems causing changes in abundance - predator prey relationships etc. Can also disrupt long reproductive cycles.

Visitors can cause direct and indirect impacts. Some of which are not noticed. Physical damage, but also temperature, acidity, changes to vibrations, CO2 levels, damage to water ways etc. - changes in streams, even very small can have big impacts.


Detailed examination of a cave species;
Tasmanian Cave Spider; Hickmania troglodytes
Is a troglophile - Loves caves but can be found outside of them. Tassie's largest spider - up to 18cm big. Example of giganticism. Builds big webs - can be a few meters in size around top of cave so that animals fall off ceiling on to web. Slow moving with slow metabolisms and can live for a long time - decades? Are halfway between old skool and new skool spiders - have some features of both. ie. fangs. Males slightly smaller than females and have kink in 2nd legs for mating things.

Courtship - males use legs to woo female - stroking her etc. Hold her body so that can mate with her but not get eaten using kinked legs. Male is often eaten after sex. Female weaves big cocoon that hangs from nest - tear drop shaped. Sometimes covers it in sticks etc. maybe camouflage? Made out of very strong anti-bacterial/ funguscide. Is unusual compared with other spiders. Thimble like inner structure so that eggs don't touch sides. Emergence time inside is long. Provides "thermos" style protection from changes in humidity and temp, shock and biotic attack. Is in a high moisture and fungus environment and stays there for 9 months yet rarely overgrown. Egg sacks can be common in caves. High humidities at the entrance and twilight zone appear to trigger emergence.

Bioresources and bioprospecting - general

Spiders are of particular interest in these fields because they are varied from each other considerably and produce interesting products in silk and venom. Silk comes in many types and offers new substances for materials etc. Venom has possibilities for pesticides - can be species specific and has different modes and sites of action etc. Also a variety of different uses in medicine. Body form of spiders is also of interest to robotics etc.

Investigation of H. troglodytes silk has been going on. Displays good anti-microbial traits, not the strongest but very long lasting - old egg sacks still have same traits.

Summaries;

Hickmania troglodytes
Evolutionary importance - a relic but also highly adapted.
Biogeographic importance.
High public interest.
Antifungal agents?
Sensitive to disurbances - air flow, moisture changes, food inflow and changes to reproductive cues etc.

Caves are highly unusual places with diverse and unusual fauna. Have unusual challenges for survival. Potential uses but also potential conservation problems. Still have direct and critical links to surface so sensitive to ground changes and disturbances.

[Jeremy]

Lecture 15

Frogs

Class; Amphiba, order; Anura (frogs and toads - not clades). Other orders of amphibians not found in Tassie.

11 species of frog in Tas, 3 of which are endemic to Tas.

Tassie frogs have three basic patterns of reproduction. Year round, such as in brown tree frog and common froglet. Bread in permanent and ephemeral water. Common froglet tadpoles are bottom dwellers while brown tree frog tadpoles swim in open water. Late summer reproduction such as in Smooth Froglet and Southern Toadlet. Use flood hollows from autumn rain and hatch as advanced tadpoles. Spring and summer. Most use permanent water except moss frog where all development is in terrestrial nest with no free swimming tadpole.

Tassie tree frogs - all have terminal discs on fingers and toes and all are pond breeders.

Threats to frogs
Most frogs require terrestrial and aquatic environments making conservation difficult. Their metamorphic stage is when they are most vulnerable. Face threats from habitat loss and modification, introduced species, loss of native vegetation and litter cover, grazing by stock, herbicide and pesticide use (pollution), UV light, global warming, chytrid fungus.

Amphibians globally are under serious threat - 32% endangered, 50% declining in number and 165 extinctions in recent years.

[Jeremy]

Truly smashed this exam. Wrote 11 pages in the 2 hours. The exam had 12 questions and you had to answer 8, but of those 12 questions most were actually two questions on the topic that you choose between - so there were actually more like 24 questions and you had to answer eight. The hardest part of the exam was choosing which to answer because I felt like I could easily answer all of them . Boom.

Also a girl in my class found this topic randomly searching the internet last night and used it to study. So hello Nadi