Adapting to climate change on subtropical reefs

Subtropical reef ecosystems with coral communities differ from their tropical coral reef neighbours, as they are shaped by a biogeographical overlap of taxa at their range margins, endemic species and seasonal species assemblages (Sommer et al. 2014). Tropical species are starting to change the biological communities living on high-latitude reefs from kelp communities to barrens and coral communities (Verges et al. 2014) resulting from range shifts and the expansion of endemic species (Figueira and Booth 2010, Yamano et al. 2011, Baird et al. 2012).Subtropical cool reef communities are shaped by highly seasonal marginal environmental conditions (Nozawa et al. 2008, Yamano et al. 2011, Beger et al. 2014, Muir et al. 2015), and undergo fast transformations as warming continues. For example, communities change along the tropical to temperate gradients according to their traits for Scleractinian corals (Sommer et al. 2014, Chong et al. 2023), molluscs (Floyd et al. 2020) and fishes (Clay et al. 2023, Clay et al. 2024). Therefore, quantifying the drivers of community assembly on subtropical reefs is an important prerequisite to predict how high-latitude reefs may be affected by climate change, and to develop conservation plans (Beger et al. 2014, Makino et al. 2014).

The management and conservation of subtropical and temperate reef ecosystems is challenged by the dynamism of the environment, and changes in community structure that already affect industries. For example, Japanese temperate fishers complain about the loss of their target fish as kelp habitats decline and are replaced by barrens or coral habitat. Protected areas have the potential to delay tropicalisation (Bates et al. 2014), and there may be options to protect sites that experience least change, or where change that is predicted to occur fits conservation objectives (Beger et al. 2014). Yet, in practice, these predictions are highly uncertain at scales relevant to management, and different climate scenarios may result in drastically different conservation priorities (Makino et al. 2015).

AIM

This PhD project aims to overcome some of the unknowns associated with reef tropicalisation across multiple taxa for a case study area in Japan. In particular, the student will quantify the ecological and functional implications of community transformations for habitat builders (corals, algae, soft corals) and associated taxa (fishes, molluscs, echinoderms). The student will apply advanced modelling tools to understand, quantify, and predict these transformations over space (tropical to temperate environmental gradient) and time (past decade, into the future). The student will then apply this new quantitative understanding towards developing new conservation theory that can be applied to work towards adapting to community transformation. The project takes a theoretical and quantitative approach, however the opportunity for fieldwork may arise. The student will work with an extensive international team in the UK and Japan, and there is considerable potential for developing the PhD in a number of directions. Depending on the interests of the successful candidate, specific objectives could include:

1. How do biophysical and biological drivers of range shifts influence ecological and functional community outcomes along a tropical to temperate environmental gradient and over time?
2. How will future assemblages change given tropicalisation? This work will involve predicting species-level and functional group level distributions into the future to examine if tropicalisation is dominated by range shifting or increasing abundance of endemics.
3. What is more important in tropicalisation: stochastic events (storms, heatwaves) vs continual warming or biological pressures?
4. How can range shifts and community reassembly under climate change be incorporated into spatial management to adapt to such changes?

SIGNIFICANCE

The focus on marine ecosystems experiencing range shifts and community transition on high latitude reefs is a highly original topic, giving this project the opportunity to contribute to shaping the field. The interdisciplinary approach involving experts in the disparate fields of physical sciences, ecology and conservation science, and its novel combination of existing datasets will allow to advance our ability to manage these ecosystems. There is the expectation that this work will directly affect marine conservation in Japan.

TRAINING

The project offers the unique opportunity to develop an interdisciplinary knowledge base encompassing, marine ecology, climate dynamics, conservation science, and offers specialist training in:

• scientific programming skills for processing and visualising large datasets;
• skills in spatial conservation decision making and commonly used decision support software;
• developing and implementing a new conservation framework with international applicability.

For further information see: Adapting to climate change on subtropical reefs – Yorkshire Environmental Sciences • Doctoral Training Network

Eligibility

The minimum entry requirements for PhD study is a 2.1 honours degree, or equivalent, in a subject relating to your proposed area of research, or a good performance in a Masters level course in a relevant subject. A first class honours degree (or equivalent) is usually required to be competitive for scholarship funding and a Masters degree is also a valuable asset.

If English is not your first language, you’ll need to provide evidence of a language qualification. The minimum English language entry requirement for postgraduate research study in the Faculty of Biological Sciences is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent. The test must be dated within two years of the start date of the course in order to be valid.

How to Apply

1) Complete the University of Leeds online application form

Select ‘NERC YES DTN Yorkshire Environmental Sciences’ as the Planned Course of Study.

The supporting documents needed to process your application are:

• certificates and transcripts of any academic qualifications
• English language qualification certificates
• visa and immigration documents

All documents should be in English or be accompanied by a certified translation into English. 

They can be sent via the online research degree application or can be emailed to ENV-PGR@leeds.ac.uk after you have submitted your application. Your email should include your student ID number (emailed to you on submission of your application), full name and your intended course of study. Please do not send original documents at the application stage and only provide documents via email.

2) Complete the YES.DTN application form. This is available on the YES•DTN website