ANSWER 1

This is a big question, and one we still have a lot more work to do on! Southern rock lobsters (SRL) are likely to be affected by ocean warming and environmental change in several ways, including changes to their physiology, interactions with other species, and their habitat. While we can predict some impacts, others still need more research.

So how might lobsters respond?
Looking at temperature effects on physiology (such as metabolism, growth, and feeding) is one way to understand responses to warming. SRL perform best between 20–22°C (Twiname et al., 2020). Average Tasmanian temperatures are below this, but summer temperatures can exceed 20°C (Stobart et al., 2016), meaning performance may decline during the warmer summer months.
SRL are also affected by other species. The range-extending sea urchin Centrostephanus rodgersii is creating urchin barrens, reducing productive reef habitat. At the same time, the Eastern rock lobster (Sagmariasus verreauxi, ERL) is extending its range into Tasmania and may compete with SRL for food and shelter. However, ERL numbers are still low, and SRL are strong competitors in food competition experiments (Twiname et al., 2022).
Warming may also affect predator–prey interactions. At higher temperatures, SRL show reduced responses to predator cues from octopus, a key predator (Briceño et al., 2018), which could increase their vulnerability.
Marine heatwaves add further challenges. Research in New Zealand shows these events can reduce lobster condition, although recovery is possible (Gnanalingam et al., 2025).
However, most studies focus on temperature alone, and we still don’t know how multiple stressors (like warming in combination with acidification, low oxygen and other human stressors) may interact. This is where more work is needed.

So how will fishing be affected?
This is difficult to predict. Changes in lobster abundance may affect local fishing spots. During marine heatwaves, lobsters may be in poorer condition, and events like algal blooms may also affect fishing seasons, as did blooms in Tasmania in 2015/16 and 2017/18.

What can you do to help?
Report any changes you see in the marine environment (i.e. via Redmap for range extending species, or to your local fisheries manager or peak body). Fishers are out on the water observing more frequently than we are as scientists, therefore you can help us by reporting any changes you see while fishing.

Briceño, F. A., Fitzgibbon, Q. P., Polymeropoulos, E. T., Hinojosa, I. A., & Pecl, G. T. (2020). Temperature alters the physiological response of spiny lobsters under predation risk. Conservation Physiology, 8(1). https://doi.org/10.1093/conphys/coaa065
Gnanalingam, G., Kelly, E. R. M., Coyle, L. J., Smith, R. O., & Allan, B. J. M. (2025). Spiny rock lobster (Jasus edwardsii) responses to marine heatwave conditions in southern New Zealand. Marine Environmental Research, 211, 107410. https://doi.org/https://doi.org/10.1016/j.marenvres.2025.107410
Stobart, B., Mayfield, S., Mundy, C., Hobday, A. J., & Hartog, J. R. (2016). Comparison of in situ and satellite sea surface-temperature data from South Australia and Tasmania: how reliable are satellite data as a proxy for coastal temperatures in temperate southern Australia? Marine and Freshwater Research, 67(5), 612–625. https://doi.org/10.1071/MF14340
Twiname, S., Fitzgibbon, Q. P., Hobday, A. J., Carter, C. G., Oellermann, M., & Pecl, G. T. (2020). Mismatch of thermal optima between performance measures, life stages and species of spiny lobster. Scientific Reports, 10(1), 21235. https://doi.org/10.1038/s41598-020-78052-4
Twiname, S., Fitzgibbon, Q. P., Hobday, A. J., Carter, C. G., Oellermann, M., & Pecl, G. T. (2022). Resident lobsters dominate food competition with range-shifting lobsters in an ocean warming hotspot. Marine Ecology Progress Series, 685, 171–181. https://doi.org/10.3354/meps13984