Hi, Raz Tamir! Welcome to ReefBites.
Raz is a PhD student in Prof. Yossi Loya’s lab at Tel Aviv University and the Interuniversity Institute for Marine Sciences in Eilat (IUI). Raz studies the spatial influence of light on coral distribution and community structure in the Gulf of Aqaba/Eilat. Read more about Raz’s work below!
Give an elevator pitch of what your research/project is about.
My current study investigates the role of the light regime (spectrum composition and intensity) at varying depths and different sites, on stony coral species distribution, and different patterns of coral community structure. We posit a novel definition for a regional or reef-to-reef outlook of Mesophotic Coral Ecosystems (MCEs) based on the light vs. coral community-structure relationship. A combination of physical and ecological methods enabled us to clarify the ambiguity in relation to the mesophotic definition. We quantify two distinct coral assemblages: shallow (<40 m), and MCEs (40-100 m), exhibiting markedly different relationships with light. The depth ranges and morphology of 47 coral genera, was better explained by light than depth, mainly, due to photosynthetically active radiation (PAR) and ultra violet radiation (UVR). I’m also studying stony corals photophysiology (i.e. functional morphology, photosynthesis, and calcification processes) at given light conditions.
Why is this research/project important and timely?
Light plays a key role in many aspects of a coral’s life circle. As such, its intensity and spectral quality at certain depths and different sites are of utmost importance for the coral’s successful colonization and distribution. Many studies to date have noted the influence of light in structuring shallow and mesophotic communities, but a combination of wide ecology surveys with light spectral measurements, supporting these hypotheses, is non-existent. My study provides some of the first detailed assessments of light levels across a broad depth range, and combined with coral assemblages’ data, offers a unique insight into the structuring of coral communities across depth gradients.
What is the broader impact and implication of your findings?
I believe that since we have come to understand how light regime controls and structures the coral assemblages along a depth gradient and among sites, we can start to refer to it as a predicted variable for the shallow to upper/lower mesophotic transition, and abandon variables as diving limits behind. More than that, besides expanding our current knowledge on the distribution of corals in the mesophotic zones, it may serve as a tool for predictive models. In addition, this deeper understanding of change in light condition due to changes in water characterizes, and its potential impact on the coral distribution and community structure, may serve as a crucial tool for decision makers.
How did you come to work in this field/project?
The main reason for this work began while I was young, as someone who was born and grew up next to the sea, this was my passion and desire to work in the marine environment with marine organisms. Above all, my hope is that this work will also have an additive value of preserving this beautiful and highly important environment, which unfortunately to date is constantly degrading. The collaboration with great people who share the same love and interests, just makes this work more enjoyable.
Location of fieldwork; why choose this location?
Eilat, Israel. The accessibility to the shallow and mesophotic reefs, make it more efficient and comfortable to perform my research. Hence, this location was most suitable for my research needs. In addition, the marine station (IUI) is a great location with many useful facilities. Besides, the reefs in the Red Sea are amazing!
Best and worst parts of your fieldwork:
The best parts of my fieldwork are the unique opportunities to work in such a beautiful environment, and the experience of working and experimenting at the deep reef while using advanced tech-diving approaches (e.g, closed-circuit rebreather). The worst part, is the fact that you have to sit for prolonged periods of time in front of the computer, while knowing that you can jump into the crystal clear water, located 50 m from your office. But hey, the results are worth it!
What advice would you give for successful fieldwork?
Before performing the research, ask yourself: “what is the question I would like to ask, and what is the best way to answer it”. Afterwards, before going into the water (especially in remote and deep sites), double check whether all your equipment is ready and works well, mainly underwater stuff (e.g. housings, probes, battery etc.).
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