The case of the invasive long-spined sea urchins, Centrostephanus rodgersii, thriving and expanding around Tasmania, mostly due to climate change impacts, offers several valuable lessons, for example:

• Ecosystem Vulnerability: The case highlights the vulnerability of ecosystems to invasive species in the face of changing climate conditions. It underscores the importance of maintaining the balance of natural ecosystems, as disruptions caused by climate change can create opportunities for invasive species to proliferate.
• Complex Interconnectedness: The case emphasizes the intricate interplay between climate change, species interactions, and ecosystem health. It shows how alterations in temperature and environmental conditions can impact species behaviour, reproduction, and interactions, causing cascading effects on the entire ecosystem.
• Adaptation and Resilience: Understanding how species adapt and thrive in changing conditions is crucial. The sea urchin's success in the altered climate sheds light on the adaptability and resilience of certain species. This knowledge can aid in predicting and managing future ecological shifts caused by climate change.
• Ecological Management Strategies: The case underscores the importance of proactive management strategies to address invasive species. Efforts need to focus not only on controlling the invasive species directly but also on restoring or enhancing the resilience of ecosystems to better withstand and recover from such invasions.
• Long-term Monitoring and Research: Continuous monitoring and research are crucial in understanding the evolving dynamics of ecosystems under climate change. This case serves as a reminder of the importance of ongoing studies to assess the impacts of changing environmental conditions on different species and ecosystems.
• Community Engagement and Education: Raising awareness and involving local communities in managing and mitigating the impact of invasive species is essential. Empowering communities with knowledge about the potential effects of climate change on local ecosystems can aid in early detection and response to invasive species.

By learning from the success of invasive long-spined sea urchins around Tasmania due to climate change, we can better prepare and develop strategies to manage, adapt to, and mitigate the impact of invasive species in the context of broader climate-related ecological shifts.

In Tasmania, invasive long-spined sea urchins, Centrostephanus rodgersii, have caused significant ecological issues in local marine ecosystems, made worse by climate change.

The sea urchins have multiplied rapidly due to a combination of factors linked to climate change. Warmer ocean temperatures have facilitated the range expansion and reproduction of these urchins. Additionally, disruptions in local ecosystems, such as overfishing of their natural predators, have led to their unchecked population growth.

Their increase in numbers and range expansion have resulted in the degradation of vital marine habitats, particularly adding to the destruction of giant kelp forests. The sea urchins graze voraciously on kelp, leading to 'urchin barrens'—areas where kelp forests have been decimated, leaving barren areas that lack biodiversity and ecological richness.

Climate change has contributed to the conditions favouring the increase of these sea urchins, exacerbating their impact on Tasmania's marine ecosystems. The combination of warmer waters, reduced predator pressure, and altered ecological balance has created an environment that allows the sea urchins to thrive, leading to significant ecological disruption around the state.

Tasmania, an island state of southern Australia, is home to various unique and important species. While there isn't a comprehensive list of keystone species specifically identified for Tasmania, several species are considered ecologically significant and could be significantly affected by climate change, such as:

• Tasmanian Devil (Sarcophilus harrisii): While not a keystone species in the traditional sense, the Tassie Devil is an iconic carnivorous marsupial in Tasmania. Their population has been greatly impacted by a transmissible cancer called Devil Facial Tumour Disease. Climate change might further stress their habitats, affecting food availability and disease spread. Extinction of Tasmanian Devils could disrupt the ecosystem as they play a role in controlling smaller mammal populations.
• Giant Kelp (Macrocystis pyrifera): Although not an animal, giant kelp plants were a vital part of Tasmania's underwater ecosystem. Climate change affecting water temperature and ocean acidification has impacted kelp growth and persistence. As a foundation species, its widespread decline around Tasmania could disrupt the entire underwater ecosystem by affecting species that depend on it for habitat and food.
• Eastern Quoll (Dasyurus viverrinus): This small carnivorous marsupial is also at risk due to habitat loss and changing ecosystems. Their extinction could affect the balance of smaller prey species and disrupt the food chain.

If any of these species were to considerably decline or go extinct due to climate change or other pressures, the consequences could be significant, for example:

• Ecosystem Disruption: Keystone species often have a disproportionately large impact on their ecosystem relative to their abundance. Their disappearance could lead to imbalances in food chains, population dynamics, and habitat structure.
• Loss of Biodiversity: The extinction of any species reduces overall biodiversity. This loss can affect the resilience and adaptability of ecosystems, potentially making them more susceptible to further changes and disturbances.
• Ecological Services Disruption: Many species provide vital ecological services, such as seed dispersal, pollination, or predator control. Their disappearance could disrupt these services, impacting the overall health and function of the ecosystem.
• Cascading Effects: The loss of one keystone species could trigger a cascade of secondary extinctions or ecological changes. For instance, if a predator disappears, it might cause an overabundance of its prey, leading to further ecosystem imbalances.

Preserving these keystone species and their habitats is crucial to maintaining the health and balance of Tasmania's ecosystems. Efforts in conservation, habitat protection, and climate change mitigation are vital to prevent the loss of these important species and their potential extinction

Climate change is affecting all of our lives in many different ways.

If you live in Tasmania, you will see it in our landscape. Sea levels are rising, which means we are losing some wetlands and beaches. This can also affect our communities. In the next few years, low-lying houses and roads are likely to go underwater. We're also getting more very hot weather days, that mean frequent and severe bushfires, which threaten some people's homes, and can destroy forests and wildlife. Because of climate change, some places, like alpine and peat bog areas that have never burned before, are starting to dry out and burn in bushfires. This means that we could lose some rare Tasmanian plant and animal species.

If you like to fish, you might find that there are different kinds of fish coming into the seas around Tasmania for you to catch - but if you like to dive or snorkel you may not see Tasmania's giant kelp forests for much longer.

By the time you are old enough to learn to drive, you are likely to drive an electric car - we need to make sure that all our transport is powered from renewable energy. And when you get a job, there will be lots of jobs that are there because of climate change - jobs in renewable energy production, jobs in climate science and climate response, new types of fisheries and agriculture and that are there because of climate change, and many more.

We will all need to be a part of adapting to climate change - and there are many opportunities to choose how you can be part of the change we need. Have a look at the What can I do? page for some more ideas.

Thanks for asking about whether there are positives from climate change.  What a great question!  Climate change is posing real challenges for people and for nature but not everything is negative everywhere.  The most obvious changes in nature include our findings that plants and animals are moving into areas where those particular species have not been before.  This is because areas further away from the equator are becoming warmer and allowing tropical and subtropical animals to move into temperate areas, and those in temperate areas to move into polar areas. In fact, polar regions in the Arctic and Antarctica are “greening” with the arrival of larger plants. 

A good example of animal arrivals in Tasmania is that Yellowtail Kingfish can be caught off the east coast of Tasmania throughout more of the year than in the past.  A citizen science project, Redmap, lets fishers log their unusual catches so that scientists can find out about these species on the move! Also, over the last 20 years, the long spine (dark blue/black) sea urchin has arrived from southern New South Wales to become very important in rocky reef systems around Tasmania.  These changes have occurred because climate change is causing changes in ocean circulation and the East Australia Current has been penetrating Tasmanian waters further and for longer throughout the year than in the past.   

Understanding whether these changes in distribution of animals and plants is a good thing or not depends on the effects those species have in their new environment.  For example, Yellowtail Kingfish live in open water parts of the ocean that have a specific temperature range.  Moving to a new open water place does not change much for the tuna or the life around it.  However, the sea urchins for example live on the sea floor and are moving into areas where there are other species that already live there.  These other species, like abalone or rock lobster, are negatively affected by the urchin as the urchin devours large amounts of algae and causes change in the rocky reef habitat.   

How can a sea urchin move from New South Wales to Tasmania if it lives on the sea floor?  Most animals and plants in the ocean have two phases in their life cycle – a larval phase (like a tadpole) and the adult phase.  Sea urchin larvae can survive in the surface of the ocean for many weeks before they settle to the sea floor.  So, larvae from sea urchins in NSW can travel on the East Australia Current and then settle in Tasmania.

You could read more about how species are responding to climate change here: https://theconversation.com/climate-driven-species-on-the-move-are-changing-almost-everything-74752 

Wow, that really is the million-dollar question, but an important one to ask! I think the most effective strategy is being engaged in whatever way you can. Climate change is a human made problem - the solutions to climate change will also have to come from us. So having passionate, curious, enthusiastic and dedicated people engaging in the process, for me, is the most effective strategy.

How you engage in this can be completely up to you! You don’t have to be a mathematician modelling carbon emissions, or an ecologist investigating the impacts of climate change on the Great Barrier Reef 😊 You can have a conversation with your friends and family about climate change and tell them why it is such a big issue and what they, you, and we all can do to take action and make a difference. You can discuss your worries for the future and the changes you would like to see. You can take part in protests about political decisions you disagree with. You can sign and share climate action petitions online. The most important thing is to make your voice heard.

There are lots of things, big and small, we can all do to help address climate change. The important thing to remember is that we should try to do something but not feel guilty if we can’t do everything. We all have different abilities 😊 Check out the Curious Climate Schools website for ideas on ways we can take action on climate.

This is a really important question – with an “it depends” kind of answer. What we know for sure is that climate change is already, and will continue to, have really big impacts. The sorts of impacts that climate scientists expect that future generations will face include more extreme weather events, sea level rise, biodiversity loss, environmental degradation – all of which have complex and interrelated flow on effects. It is also important to remember climate change is not just a problem that is going to have impacts in the future. It is already having significant impacts to people’s lives right now!

What’s tricky about this question is that the kinds of impacts and extent of those impacts that future generations will experience however, depends on different mitigation scenarios. What that means is that if action is taken now to reduce greenhouse gas emissions and reach net zero CO2 emissions, then the scenarios for future generations will be less severe and dangerous then if action takes longer or doesn’t happen at all. What is also tricky about this question is that projections of what the future may look like depending on current actions could be much more severe and extreme if we reach ‘tipping points’ (some of the other experts have answered questions about these).

One of the really helpful things about these climate models and scenarios is that they show us really clearly what we need to do now to ensure a safer world for future generations. We can be a part of creating a more just and safe world for future generations by taking action now.

You could also read these articles about climate projections for 2500, and what the earth will be like 500 years from now.