JOL – Week 13. Marine Conservation & Habitat Mapping.

Marine Conservation & Habitat Mapping.
Find an example of a pipefish that is classified by the IUCN Red List as critically endangered and one that is least concern. Explain how differences in the biology of the two species might contribute to differences in their status, and on what basis the classifications were made.

Least Concern: Cosmocampus arctus – Snubnose Pipefish.

Critically endangered: Syngnathus watermeyeri – River Pipefish.

Differences in biology: Snub-nose pipe fish prefer marine environments such as coral reefs and rocky outcrops. River pipe fish prefer the estuary environment (Brackish waters) and can survive in both fresh and marine water environments.

This may contribute to their differences in the way that they inhabit different environments and so have different predators and different sources of food. River pipe fish rely heavily on the Eelgrass that makes up their habitat and zoo plankton to eat.

These classifications were made on the basis that there are a large number of Snubnose pipe fish in the wild, as they have minimal predators and no loss of habitat. The Rover pipe fish is considered critically endangered due to the building of dams that have destroyed the habitat and water circulations required for the River pipe fish to eat and live.

Identify two marine species listed as Critically Endangered, Endangered, or Vulnerable in NSW, and explain why the species is listed as such.

Scalloped Hammerhead Shark – Sphyrna lewini – ENDANGERED.
The Scalloped Hammerhead shark is considered to be a endangered species for the following reasons;

·      Poor recovery ability.

·      Large amount of fishing of this species.

·      Fishing of juveniles by gill-nets and trawl nets.

·      Fishing of adults by gill-nets.

·      Shark fins (large and valuable) & meat for eating and medicine.


Great White Shark – Carcharadon carcharias – VULNERABLE.
The Great white shark is considered to be a vulnerable species for the following reasons;

  • Females do not produce offspring till they are of a certain maturity.
  • They do not produce offspring every year.
  • Females produce few pups.

This suggests that if they were to become endangered it would take a long time for the species to recover.

  • Decline in species due to commercial fishing and entanglement in mesh netting.

In your blog, summarize how no-take zones work and when and where they are most effective.

No take zones work in the way that all commercial and recreational fishing is prohibited. This means that no animals are allowed to be removed from the waters in these areas.

They are instigated by the government to help protect certain ecosystems and environments. They are largely found in marine protected areas such as Marine parks and reserves. These areas already have moderated human activity to preserve the ecosystems and environment. The no take zones takes it one step further and bans all extraction of resources from that area.

In your blog, summarize the three types of zone present in NSW marine parks, and what types of activity are allowed within each. How are the three types of zoning distributed relative to one another, and why do you think this is the case?

The three zones include:

General Use zones, Habitat protection zones and Sanctuary zones.

The types of activities allowed in each area include: (As per Information from Jervis Bay marine park)

General Use Zones Habitat Protection Zones Sanctuary Zones
Line Fishing Line Fishing Boating
Prawn hauling Scallop Collecting Snorkeling/ Scuba diving
Spearfishing Spearfishing
Collecting for bait/food Collecting for bait/food
Boating Boating
Snorkeling/Scuba diving Snorkeling/Scuba diving
Anchoring Anchoring

For research, collecting for science or research, whale watching and spearfishing/sailing competitions permits are required.

They are distributed relatively differently. There are minimal areas for General use and much more Habitat Protection zone than Sanctuary Zone. I believe this is the case as it is a national park that is home to a large number of different marine creatures. Its where Port Jackson sharks, Hammerhead sharks and Bronze Whaler sharks come to mate and breed, Its home to a number of seal colonies, whales pass through during their migration season. The zones are put in place to preserve these environments and protect the species that use the bay.

The General use areas, are provide so people can still participate in the activities they like to do when at the beach, but provides a guideline and rules that minimalize the effects of these activities on the wildlife within the bay.

Using the maps, describe the distribution of key habitats in two NSW estuaries of your choosing. Explain how these habitats might contribute to the ecosystem services provided by the estuary.

Wamberal, Terrigal, Avoca and Cockrone Lakes: Provides two large habitats for Ruppia (A type of marine plant also knows as ditch grasses or widgeon grass). Does not show any other types of habitat.

Moruya River and Congo Creek: Shows a number of different habitats including Saltmarsh, Zostera (sea grass), Halophila (Sea grass) and Mangroves.

These habitats may contribute to the ecosystem services in the form of:

  • Habitat – Different types of places for different species to live – i.e mangroves.
  • Food – Sea grasses/marine plants provide food and shelter for marine organisms & humans.
  • Materials – Mangroves used for building etc.






Letter 2 – Managers View.


Dear Stakeholders,


Firstly I appreciate the correspondence received in regards to the Proposal to permit the cultivation of triploid Pacific oysters in NSW estuaries. Your views and concerns have been reviewed. You are receiving this letter to help provide an understanding of the situation and the decisions that have been made at this current time.


The devastation that QX disease has caused throughout the Hawkesbury river region is a primary concern. Hawkesbury river oyster farmers produce over half of all NSW oysters. It’s incredibly important not only on an ecological standpoint but also from an economic position to take all necessary measures to not only look into preventing QX but also other alternatives to keep the Hawkesbury river oyster industry alive.


Previously researchers have looked into disease prevention strategies for QX disease. This incorporated the use of disease zoning to help control spread. However due to the multiple factors that fuel QX, such as environmental stressors as well as the parasite Marteilia sydneyi, the disease continued to spread throughout the region. There was also an implication as spat is required to be transferred between estuaries in order to increase populations. This enabled the QX disease to spread further and faster than anticipated.


The proposal to permit the cultivation of triploid Pacific oysters in NSW is the next step in helping to get oyster farmers back on their feet. As expressed through your correspondence there were many concerns in regards to the introduction of this species in NSW estuaries such as the possibility that Pacific oysters could become reproductively capable. Farmers will be provided with literature in regards to maintaining their farms and fisheries officials will monitor the farms for the first 4 years of cultivation. With effective management the prevention of uncontrolled spread should not be a long-term problem.


The benefits for this proposal far outweigh the concerns in this instance. Summarized below are the main key benefits that have shaped the decision to implement this permit.

  • At this present time the cultivation of Pacific oysters in the Port Stevens region has been a success. There have been no major ecological impacts in regards to cultivating this species observed to date.
  • As Hawkesbury River oysters are such a large percentage of commercial farmed oysters in NSW it is important to find an alternative with proven resistance to mass mortality diseases such as QX and Winter mortality. The Pacific oyster is resistant to both of these diseases.
  • Pacific oysters are found to be 4.1% heavier, have a higher dry meat and condition index than Sydney Rock Oysters after a period of 2.5 years of growth. This indicates a fast growing, possibly larger product than previously grown, with a high standard of quality.
  • Pacific oysters grow to the standard market size 6-18 months faster than Sydney Rock Oysters, providing a larger supply to customer demand.
  • Oyster farmers have the potential to earn a higher living, as these oysters can be cultivated all year without any disease related disturbances. Farmers also have the potential to reduce overall costs in regards to disease prevention and loss of income due to outbreak.




It is with great consideration and intensive research that this next step in oyster disease control is implemented in the Hawkesbury river region. The underlying factor is that without the introduction of Pacific oysters, the Hawkesbury River oyster populations will inevitably die out. This would not only be a major loss to the income and livelihood of oyster farmers in the region but also to the estuary environment and consumer.






Mr Neill Blair,

Minister for NSW Department of Primary Industries.

20th May 2015.




Fisheries NSW

Port Stephens Fisheries Institute

Locked Bag 1, NELSON BAY NSW 2315

Tel: 024982-1232 Fax: 02 4982 1107

ABN 72 189 919 072



  1. Green, T., Raftos, D., O’Connor, W., Adlard, R.D., Barnes, A.C., 2011. Disease Prevention Strategies for QX Disease (Marteilia sydneyi) of Sydney Rock Oysters (Saccostrea glomerata). Journal of Shellfish Research, Vol 30, pp.47-53.
  2. Nell, J.A., Cox, E., Smith, I.R., Maguire, G.B., 1994. Studies on triploid oysters in Australia. I. The farming potential of triploid Sydney rock oysters Saccostrea commercialis (Iredale and Roughley). Aquaculture, Vol 136, pp. 243-245.



JOL Week 12 – Marine eco tourism.

Based on the articles and your own understanding, list some pros and cons of ecotourism.

Ecotourism can have both pros and cons in regards to conservation.

  • Greater understanding. Eco tourism can have an educational element; where as part of the experience is based around conservation and education and how this knowledge can be implemented to help in the future.
  • Money generated through eco tourism helps to support conservation efforts and also supports local communities.
  • Eco tourism enables for land to become “reserves” rather than just public ground. This offers a little bit more protection to the animals living there. Also these areas are made to be of importance as if people are going to continue to come and see the animals they need to be protected so that the tourism aspect stays in effect.


  • Mistreating of animals – Animals being used for entertainment purposes – Orcas at Sea world. Taken from their natural habitats and used as an income generator.
    – Recreational fishing – Caught & released, still causing stress and injury to animals.
    – Whale/dolphin watching – whales and dolphins become stressed and change feeding habits, migration patterns
  • The more people who participate in eco tourism the bigger the footprint left behind – damaged habitats, pollution etc.
  • Travel to these destinations (via cars/planes etc) causes pollution – has a direct link to climate change.
  • Money in the way of fees etc are not always put towards conservation efforts.


Summarise how whale watching is regulated in Australia and, drawing upon your knowledge of how whale watching can impact whale behviour, explain how these regulations would reduce whale-watching impacts

In Australia, Whale watching is regulated in a number of ways including:

  • All vessels must not purposely approach a whale closer than 100m. If a whale has been sighted within a 300m radius all vessels must travel at a lower speed and be vigilant for activity – If the whale moves, submerges etc.
  • All feeding or physical contact of whales or dolphins is prohibited. So absolutely no feeding the animals or touching them, under any circumstance.

The ways in which these regulations would reduce whale-watching impacts include:

  • If vessels are limited to 100m of the whale it gives it a decent amount of space to resume what it was doing, e.g. keep travelling in the direction it was going. By preventing closer encounters, whales will (hopefully) not be too disturbed by the presence (wake) and noise from the vessels. Enforcing vessels to travel at a lower speed within 300m of each whale would also decrease the noises from the vessel and enable the whale to not feel threatened.
  • By preventing physical contact and feed whales will obviously not be threatened by the presence of people but not be bothered with whatever might be fed to it. Disrupting its feeding patterns by feeding the whale directly may cause it to lose its natural instinct to hunt/feed.

    Whale Watching - Foster Photo taken by Rachael Steel.
    Whale Watching – Foster
    Photo taken by Rachael Steel.

On the whole, do you feel whale watching is of net benefit or detriment to whale populations? Explain your answer.

On the whole I believe whale watching has both negative and positive effects. I personally have been whale watching numerous times. I loved the experience of being able to see these creatures in their natural habitat, and depending on the charter you go through many of the tourism guides have an extensive knowledge of the animals and contribute towards educating the general public on how to conserve and protect these animals. Lots of these charters also donate profits to whale conservation groups.

I believe if the guidelines are followed correctly and enforced harshly with threats of fines, loss of boating/business licenses there shouldn’t be a problem to the whales themselves.

As long as they don’t feel threatened, don’t have to alter their natural behaviors, i.e feeding, changing directions due to boat activity etc we should be able to experience them in their natural habitat.

I STRONGLY believe this is a much better approach than catching them and keeping them in tanks/small pools at places like sea world (USA).

Do you support the continuation of ecotourism based around shark-feeding dives? Why/why not?

In regards to shark-feeding dives I understand both the negative and positive aspects. Firstly I would do ALMOST ANYTHING to be able to do one of these dives. It’s my life’s dream to be able to swim with sharks and appreciate them in their natural glory, Tigers, Great whites and Whale sharks, all of them if it’s possible!

However, I do understand that these activities and the baiting techniques used to attract the sharks may be causing them harm. i.e associating humans with feeding and causing them to not use the full potential of their natural instincts to hunt (get lazy). I also understand that having such regular contact with humans may change their overall behaviors in regards to human influence. Ecological factors such as if these sharks do become lazy and decide that this bait is their easiest source of food their prey species will increase causing ecological problems to their natural habitats.

I support the continuation of these dives – mainly because I think they enable humans a better understanding of what amazing creatures sharks are. There is no comparison to watching a shark on TV and being in a cage, only meters away from one. There is no way one can appreciate the sharks and how truly important they are to ecosystems and the oceans in general, without seeing one in the flesh (in a safe way). With shark finning still a major issue throughout the world, these dives can also be used as a conservation system, to educate the public and inspire them to help.

However for this to work, regulations have to followed.

The dives should be limited to a number per day – so the sharks aren’t continuously being subjected to human contact and feeding.

The chum should be just that – chum, not actual bait, if the sharks aren’t getting fed they still have to use their natural instincts to find food – they may still associate humans with the smell and taste of food but without actually eating its possible they’ll remain disinterested. – It’s all down to mistaken identity.

Although I am opposed to animals in captivity in many circumstances, I believe that the program run by Manly Sea-Life aquarium – Shark Dive, is a great way for people to encounter these creatures. Although not in their natural habitat the sharks are kept for conservationist/rehabilitation purposes and the participants of each dive are given tonnes of information on the life of these creatures and how best to protect them for the future.

Shark Dive. Manly Sea life aquarium.
Shark Dive. Manly Sea life aquarium.

In your blog, discuss whether the benefits of tourism in Antractica outweigh the costs, giving your rationale.

In regards to tourism in locations such as Antarctica the paper by Elijgelaar et al. (2010) J Sustainable Tourism 18, 337–354 concludes that the cost is higher than the benefits. This was found in the way that people who participated in these cruises did not acknowledge the conservation aspect as much as predicted. The paper founded that the Co2 emissions from the ships conducting these cruises plus the emissions from passengers travelling (car/plane) to get to the cruise terminal and home again where higher than other cruise liners.

This seems to me to be more of a negative impact from tourism. If conducting these cruises are only worsening the already evident climatic effects to regions such as Antarctica then I don’t believe the benefits outweigh the costs.
I imagine that SOME people who embark on these trip do grasp an idea of the situation in regards to climate change and the glacier deterioration and may change their overall views on living a “green” lifestyle, however if the ships themselves are only worsening the situation it may not be worthwhile having 20/100 passengers go home with a new conservation mind frame when the ship itself has already caused more damage.

Week 11, JOL – Oceans and estuaries as transport systems.

How has the number of marine invasions attributable to shipping changed over time? Why do you think this is the case?

Over time the number of marine invasions has dramatically regards to shipping with an approx. jump from 40 to 80 invasions over a 30 year period.
In regards to fisheries, the number of invasions has also continued to increase however not to the extent as shipping.

This is possibly the case due to the shipping industry expanding. As shipping and marine transportation has become a primary method for transporting goods from one location to another so has the number of invasions increased.

Fisheries have become more controlled in the way of policing and rules and regulations being implemented.

Find an example of a marine organism that is thought to have been introduced to Australian waters by shipping. In your blog, provide a picture of the species (this does not need to be original but please acknowledge its source), a brief description of how it is thought to have arrived in Australia and how its spread is presently being managed.

Asian Green mussels are considered to be an organism that was introduced to Australian waters by shipping.


These organisms are likely to have been introduced by “hitching a ride” on the bottom of transport ships. As they are a fouling organism. When the ships reach Australian ports it is possible for them to release eggs, or become unattached from the ship, hence being left behind. The Asian green has been found among biofouling on vessels in WA ports.
The spread is being managed by advising ship and boat owners to be vigilant and to carefully inspect and monitor their vessels for these organisms.

In your blog, explain how boat wake can impact the ecology of estuaries, and describe strategies of management that may be put in place to minimize the impacts of wake

Boat wake can have a large effect on the ecology of estuaries.

The high energy and long lasting waves created from boats such as “Kelvin wake” can cause erosion to the banks of estuary systems as well as upset the invertebrates living in the embankments.

Internal wave wakes can disrupt the ecology of the water by mixing up its different layers e.g. Oil slicks.

Over time the wake from boats and ferries has made evident extensive erosion damage to estuary systems such as the Northern Parramatta river. The repeated breaking of these boat caused waves against the banks of the river have caused it to erode over time.

In order to manage and minimize the impacts of wake to estuary ecosystems, introducing “No wake zones” to certain highly damaged areas as a form of recover could help to rebuild or at lease preserve what is left of damaged areas. This means that boats can only travel at a certain speed/certain locations to enable minimal to no wake within that water system.

Another idea is introducing vegetation such as mangroves to act as a barrier between the wake and the shoreline.
In your blog, summarise the ways in which mooring buoys impact seagrass and the mechanism by which ‘seagrass friendly’ mooring buoys reduce this

Mooring buoys can impact seagrass in the way that anchors can cause damage. When the anchor is dropped it crushed the vegetation underneath. If the anchor is moved, this also causes it to uproot the vegetation in its path.

“seagrass friendly” mooring buoys reduce this damage in the way that that provide more flexibility for the anchor that previous dump and chain systems. Rather than the previous method, seagrass friendly mooring system uses rope and a single hold on the ground, which keeps the rope above the seagrass levels. It uses pullies and leavers to enable to rope to move with more flexibility resulting in sea grass not being ripped out my moving chains.

In your blog, explain how the habitat provided by pontoons, pilings and seawalls differs from that provided by natural rocky reef, and the implications of these differences for coastal biodiversity.

The differences between artificial habitats in comparison to natural rocky reefs include:

  • Pontoons are a floating structure whilst rocky reefs and pilings are fixed structures.
  • Pontoons sit on the water line and are mostly in the surface waters, whereas rocky reefs and pilings have more depth and can support different organisms due to temperature and light availability. (Reefs being deeper overall than pilings)
  • Differences in shading. Artificial structures come in more clustered format and so create more shade. Rocky reefs do not cause as much.
  • More vertical structures in artificial structures than in rocky reefs.
  • Both support completely different communities or organisms.

The implications of these differences for coastal biodiversity include:

  • Different types of organisms found at the different locations.
  • Artificial structures (pontoons) appear to have more invasive species that rocky reefs as they create a bare habitat for them to live in. – Creates stepping stones for invasive species to inhabit.

Letter One

Rachael Steel

19 Crown Road

Umina, NSW, 2257

May 5, 2015


The Hon. Niall Blair, MLC

Minister for Primary Industries, Minister for Land and Water.

NSW Department of Primary Industries

52 Martin Place

Sydney, NSW, 2000


Re: Permit to cultivate Pacific Oysters in the Hawkesbury River estuary system.

Dear Mr Blair,

I write to you today out of concern for my future and the future of the native oyster industry within the Brisbane Waters region. A friend of mine that farms oysters in the Hawkesbury River has bought to my attention your idea to start cultivating non-native Pacific oysters as a way to beat QX disease. I understand the thought behind the idea, as a farmer I can understand how hard it would be to lose my stock to a disease like QX however I’m concerned about whether this is the best solution and that it may result in further problems along the line.
As I’m sure you’re aware, QX disease is widespread. However, there are many instances where QX is yet to be found. My farm is located about 33Km from Hawkesbury River, in the Brisbane Waters catchment near Gosford. Currently QX disease has not affected my stock at all. Although at the moment the coast is clear I’m worried about my future and that of my business and family if QX is to eventually find me.
I’ve done some research into triploid Pacific oysters and have a few concerns about introducing them as a replacement for Sydney Rock Oysters.

1.     Their ability (however slight) to reproduce.

2.     Other diseases

3.     Appearance and customer demand for local produce.

I’m aware that currently Pacific Oysters are being farmed for aquaculture in Port Stevens NSW without an issues. However elsewhere within NSW these oysters are considered to be a foreign pest and overseas there has been issues with this species. Have we not learnt our lesson with introducing “pests” into our ecosystems? Look at the Queensland Cain toad for example, they were introduced to help and combat a problem, only to become a bigger problem themselves. How can we be sure this will not happen with the Pacific oyster? I don’t believe one example in Port Stevens in enough to support an entire idea. Although their ability to reproduce is low it’s still a possibility. It may take years and years for them to reproduce enough to create a problem but what do we do then?

My next concern was that other diseases, other than QX may cause the exact same problem among the Pacific Oyster populations. I’ve done some research and found an article about mass mortality in commercially farmed Pacific oysters in the Hawkesbury River from a disease called Ostreid herpesvirus -1. This seems to be fixing a short term problem only to deal with it again later.

My final concern was the appearance of the Pacific Oyster in comparison to the Sydney Rock oyster. I read another article that warned that Pacific oysters undergo changes to the shape of their shell, which makes them less attractive.
The Brisbane Water Oyster Festival is held in November each year at the Ettalong Beach waterfront. The festival allows local oyster farmers to sell their oysters. It is extremely important to me to have the best produce for my customers at this event in order to boost my income and support my family and business.

I believe that with further research there may be other methods of saving the Sydney Rock oysters from QX disease. I request look further into the matter before making any firm decisions that may affect the oyster industry for everyone, not just those affected by QX disease.


Thank you and regards,

Rachael Steel.
Sydney Rock oyster farmer from Brisbane Waters.










Bishop, M. J., Krassoi, F. R., McPherson, R. G., Brown, K. R., Summerhayes, S. A., Wilkie, E. M., and O’Connor, W. A. (2010). Change in wild-oyster assemblages of Port Stephens, NSW, Australia, since commencement of non-native Pacific oyster (Crassostrea gigas) aquaculture. Marine and Freshwater Research 61, 714–723.

Green, T., Raftos, D., O’Connor, W., Adlard, R., Barnes, A. (2011). Prevention Strategies for QX Disease (Marteilia sydneyi) of Sydney Rock Oysters (Saccostrea glomerata)

Journal of Shellfish Research, 30, 47-53.

Paul-Pont, I.,  Evans, O., Dhand, N., Rubio, A., Coad, P.,  Whittington, R. (2014) Descriptive epidemiology of mass mortality due to Ostreid herpesvirus-1 (OsHV-1) in commercially farmed Pacific oysters (Crassostrea gigas) in the Hawkesbury River estuary, Australia. Aquaculture, 422, 146-159.

Week 10 – Journal of Learning.

Carbon cycling in Coastal Environments.


How does the primary productivity, per unit area, of coastal primary producers compare to that of marine primary producers. Why, then, do you think oceanic primary productivity is greater overall? Write about this in your blog.

Coastal primary producers 10% of all marine production
Marine primary producers 90% of all marine production.

This is surprising as there is a larger number of organisms that enable primary productivity within coastal regions i.e. mangroves, coral reef algae, seagrasses etc. Whereas in the marine environment the main primary producers are phytoplankton and on occasion floating seaweed debris.

I believe oceanic primary production is generally much higher than coastal primary production due to the overall size of the ocean in comparison to that of coastal regions. The area of the ocean is much larger than the area of coastal regions. This means that there although there are fewer types of primary production in the ocean in comparison to the coast, there is a much higher volume of that particular primary producer (phytoplankton) due to the availability of area.


Explain where marine primary production is greatest, and why this is the case.

Marine primary production is greatest in coastal regions. This is due to a range of factors including temperature, currents, light and water movements (upwelling & down welling).

Upwelling is the process of a movement of water being forced upwards towards the surface. This water is pushed up from the colder deeper water and contains an abundance of nutrients. These nutrients are what stimulates the phytoplankton.
Upwelling do not happen everywhere (less than 1% of the world’s oceans) however they are responsible for more than 20% of the world’s oceans productivity. This could be due to currents transporting primary producers from one location to another, allowing for a greater dispersal of producers regardless of how restricted upwelling is.

Wind also has an effect in the way that is acts as a conveyor belt and pushes the coastal primary producers out to seas and draws in the ocean producers closer to the coast. Light also has an effect on coastal primary production as light can only penetrate the water so far, light/photosynthesis is what supports primary production. Without light, benthic producers cannot produce.


Of the marine primary producers included in the figure, which have the greatest carbon storage? Why is this the case?

Seagrasses have the greatest carbon storage. This is due to seagrass having the ability to store carbon in its roots and soil. According to a study by J.W. Fourqurean seagrass meadows store up to ninety percent of their carbon in the soil and are able to continue to build on these amounts of carbon for centuries.

Fourqurean, James W., et al. “Seagrass ecosystems as a globally significant carbon stock.” Nature Geoscience 5.7 (2012): 505-509.


Explain how coastal wetlands sequester and store carbon.

Sequester: Within coastal wetland environments plants collect carbon from the air and use it to produce their leaves, roots and stems. In turn plants also release carbon dioxide after using the carbon to produce energy – this is photosynthesis.
Storage: Carbon can be stored in the leaves, roots and stems of plants. When dead parts of these plants fall to the ground they are often covered by tidal waters (wetland environment), because of this the plant materials take a long time to break down allowing for carbon to remain stored. Carbon can also be stored in the surrounding soil, for example when a plant dies the carbon is released into the soil as the root system dies. It can stay trapped for many years.

What are the key threats to blue carbon, and how might these be curbed?

The largest threat to blue carbon is clearing of mangroves, saltmarshes and seagrass in order for further urbanisation (coastal development) and aquaculture (farming).

The loss of these aquatic plant life causes the sedimentation to mix, releasing carbon that may have been trapped for extended periods of time. When this carbon is released (CO2) it goes back into the atmosphere causing many issues in regards to climate change etc.
It is suggested that the loss of these ecosystems is causing approx. 500 million to 1 billion CO2 tonnes to be released into the atmosphere per year.

As banning coastal development entirely seems impossible – due to the need of land, urbanisation and aquaculture economy (fishing for money, food etc) in developing countries, I believe there needs to be a better monitoring system put in place.  If a location can be tested and found to contain blue carbon deposits then that area can be protected, this enables the protection of high stores of carbon however still allows for developmental growth along the coast. Incentives may also help in the way that people are offered lower prices for land in areas where blue carbon deposits are found to be lowest/non-existent in comparison to locations where blue carbon deposits are highest and “Protected”.

Journal of Learning – Week 9. Marine renewable energy sources.


In your blog, describe the four types of marine renewable energy and discuss which (if any) are most feasible for Australia.

Mechanical Energy:
Wave energy – Wind waves and long period swell. Wind waves are created by winds pushing the surface of the ocean to create waves. These waves are not incredibly powerful. Long period swell entails waves created by storms, these waves are often much more powerful and can travel much further distances.

Tidal energy – Is based on the tides. Tides are based on the force of gravity from the moon and sun reacting and manipulating the earth and oceans. This type of force causes the oceans to “bulge”, this in turn creates long waves. There are two main types of tidal energy (Tidal barrage and tidal current).

Thermal energy:
Heating from the sun. The temperature difference in warmer surface waters and cooler deeper waters.

Energy from ocean currents from such currents as the EAC produce energy in their movement.


The most feasible for Australia would be Tidal energy. Wave energy requires wind or storm activity to create the waves required to produce the energy. Unfortunately as Australia’s climate is so diverse and weather so unpredictable it cannot be guaranteed that there would ALWAYS be wind to produce the waves. In some parts of Australia (Southern Australia & Northern Australia) strong winds and tropical cyclones may be more feasible however this is only in certain locations throughout the country and at certain times during the year.
However with the tidal energy, as the Earth is constantly under the influence of gravity tides will always occur at most marine – meets – land locations (beaches, rivers, etc) This suggests that tidal energy would always be constant and therefore a more feasible source of energy that wave energy, which cannot be counted on to always be able to be produced.


In your blog, discuss how energy can be harvested from waves.

Wave energy is all about creating a rotation – this in turn creates electricity. The energy itself comes from the movement of the wave, not the wave itself. As the wave moves, a certain point (vertical) will rise and fall with the wave motion. As this movement occurs it can push a wheel causing it to rotate and produce energy. The vertical movement will produce the rotational movement. – Produces electricity.

Two floating objects (connected via connector in the middle) as the waves rise and fall, so will the objects causing the connector to flex with the motion. This will cause it to again have a rotational movement producing energy.

Research how each of these three main forms of tidal power generation work, and summarise each in your blog.

  • A tidal stream generator – Can also be referred to as a TEC (tidal energy converter). It is a machine used for removing energy from tides (moving masses of water). These machines work a lot like a wind turbine in the way that they take the energy from currents in the water like wind turbines collect energy from the air. The water flow creates a rotational movement in the tidal stream generator which produces the energy. It is advised that this is the cheapest and least economically damaging of the three main forms of tidal power generation.
  • A tidal barrage – Acts a lot like a dam. It captures the energy from the water as it moves in and out of the area during high and low tides. However instead of damming water like a normal dam would a tidal barrage collects the water as the tide pushes in it in and releases the water as the tide goes out again. This is monitored by someone who measures the flow of the tides and controls the sluice gates when it is required at certain points during the tides. This is one of this oldest methods of tidal power generation.
  • Dynamic tidal power – Has yet to be tried and tested, however it involves a dam like structure (much like tidal barrage) however much longer the is built perpendicular to the coastline – It leaves an option for a coast parallel barrier at its far end which would form a T shape, however this is not compulsory for it to work. It produces energy in the way that the dam would interfere with the tides creating different water levels on each side of the structure. These different water levels would drive a number of bi-directional turbines (Like tidal stream generators) which would produce the energy.

DTP Diagram

In your blog, summarise the costs and benefits of offshore wind farms


  • Hypothetically a 500MW wind farm, consisting of 100x, 5MV turbines – in shallow water 15miles from the coastline would cost an estimate of $340 million for the turbines, $100 million for the foundations for the turbines, $60 million for all of the electrical connections. This gives an estimate of the total construction cost being $1200/kW and energy costing $54/MW h.
  • Other costs include annual expenses of land rent – $12,000.00, maintenance – $215,000/year, Replacement & overhaul costs – $55,000/year.
  • As they are positioned in the ocean, it may be harder to access and complete repairs maintenance etc on them due to their location.


  • Wind power has low carbon emissions over its life cycle. Meaning that it appears to be environmentally friendly and has little negative impact on the environment (No toxic emissions etc).
  • Wind power does not require fuel to operate. Meaning there is no fuel costs to run this machinery.
  • There is no dependency on freshwater to power the machinery which other conventional sources do require.
  • Offshore wind power has the benefit of location – its structures are not taking up land space that could be used for farming ect but are placed in the ocean where winds are more and space is less usable.