Event

UNOC: Our Ocean Future – Empowering the Next Generation of Ocean Leaders

Our Ocean Future - Empowering the Next Generation of Ocean Leaders

At the 2022 UN Ocean Conference held in Lisbon, the Bertarelli Foundation co-hosted with IOC UNESCO and ZSL an official side event on the morning of Tuesday 28th, June titled ‘Our Ocean Future – Empowering the Next Generation of Ocean Leaders’.

Marine scientists are at the heart of science innovation, translating scientific conclusions into management practises, and increasingly the move towards sustainable development. The technical capacity of ocean science remains unequally distributed among countries and regions, particularly in infrastructure, deep sea exploration and data management. While the number of scientific publications continues to increase, they are heavily skewed in origin and focus to the Global North. Networks of early career marine scientists are central to the innovation of transformative solutions. These networks can be further improved by encompassing diversity of disciplines, racial diversity, and gender. However, the contribution young marine scientists and conservationists can make is often overlooked and the level of support offered to them differs widely among countries. This event took the form of a conversation between three ocean leaders and three ocean youth from the Global South, with the goal of identifying clear actions to overcome barriers and accelerate opportunities for next generation ocean leaders.

Panellists

Ocean leaders:

Professor Rashid Sumaila (University of British Columbia, Canada)
Angelique Pouponneau (Alliance of Small Island States, UN Decade of Ocean Science for Sustainable Development Advisory Board,
Dr Asha de Vos, Oceanswell, Sri Lanka)

Ocean youth:

Inès Boujmil (BlueMed Ambassador in Tunisia, Fisheries & Environmental Engineer at National Institute of Marine Sciences and Technologies)
Camille Rivera (Oceanus Conservation, Philippines)
Sivajyodee Sannassy (Bangor University, UK)
Lasuni Chathurima Gule Godage (Ocean University of Sri Lanka via video message).

Moderated by: Professor Heather Koldewey, Lead, Bertarelli Foundation’s Marine Science Programme, Zoological Society of London, with an introduction by Dona Bertarelli, Bertarelli Foundation, and Alison Clausen, IOC UNESCO, with concluding comments from Dr Sylvia Earle, Mission Blue.

The recording of the live-event is available to watch below:

Improving MPA Management

New Marine Science Seminar Series Launches 15th September

The first of the Bertarelli Foundation’s monthly marine science seminars will take place on 15^th September. This online seminar series will invite experts to share their knowledge and experience as we explore important marine science questions and conservation challenges.

This first session will take place online at 1pm (BST) on Tuesday 15^th September and will discuss holistic approaches to island restoration. Chaired by Prof. Heather Koldewey, she will introduce four speakers who are all working on the interface between tropical islands and coral reef systems.

Intact island ecosystems are vitally important for biodiversity conservation. However, more recently, researchers are also considering the role that island ecosystems also play in supporting the health of neighbouring reefs.

Following the short ten-minute talks, attendees will have the opportunity to ask questions – or provide their experience – about this increasingly important topic.

Seminar: Rats, Seabirds and Reefs: Holistic Approaches to Island Restoration

When: Tuesday 15^th September 1pm (BST)

Chair: Professor Heather Koldewey (Zoological Society of London)

Speakers:

Sarah Havery (RSPB) – The Importance of Removing Invasive Species

Sarah Havery is a Senior Species Recovery Officer for the Royal Society for the Protection of Birds (RSPB) based in the UK. She received her BSc. (Hons) in Biology from the University of Bristol and her MSc. in Conservation and Biodiversity from the University of Exeter. Sarah has been directly involved in habitat and species recovery work on islands in the Indian Ocean, the South Pacific, the Caribbean and in the UK. Her role at RSPB involves managing conservation programmes to support the recovery of globally threatened species in the UK Overseas Territories and in east Africa. Sarah is also a trustee for the Chagos Conservation Trust and is supporting the development of their Healthy Islands, Healthy Reefs programme.

Dr Araceli Samaniego-Herrera (Landcare Research) – Rat Eradication on Tropical Islands

Araceli’s niche is at the intersection between biodiversity conservation and applied research. As a conservation manager, she has led numerous conservation projects on islands, including 12 rodent eradications—all successful. Her 18-year career in island restoration started in Mexico and expanded internationally to countries including Australia, Belize, Canada, Fiji, French Polynesia, New Zealand and the USA. As a conservation scientist, she aims to advance restoration methods particularly for tropical islands, where challenges are more complex. She uses and promotes technological innovations to maximise conservation effectiveness. She recently joined Landcare Research (New Zealand) and is excited to contribute to awe-inspiring projects such as Predator Free New Zealand.

Peter Carr (University of Exeter) – Is Rat Eradication Enough to Rewild Tropical Islands?

Peter first visited the Chagos Archipelago in 1996 and has been committed to the conservation and rewilding of the islands since. Author of Birds of BIOT (Carr 2011a) and numerous articles and papers on the area’s natural history (e.g. Carr et al. 2013, Carr 2014, Carr 2015), as part of his PhD, he has recently published the definitive account of the breeding seabirds (Carr et al. 2020). While working on Diego Garcia (2008-2013) he raised the funds and led the restoration of the largest expanse of freshwater in the central Indian Ocean, now home to all species of the region’s dragonflies (Carr, 2020). He also 50% funded and led a trial of rewilding abandoned coconut plantations, successfully converting 30 hectare of plantation back to native forest – this project gave the opportunity to over 200 people to become involved in conservation activities on Diego Garcia (Carr 2011b). In 2014, Peter led the first successful eradication of rats from an island in the Chagos Archipelago (Harper et al. 2019). In 2019, he spent eight months on Lord Howe Island as a team leader on the largest rat and mouse eradication project of its kind in the world. Peter is presently finishing his PhD and, is part of the steering committee working towards rewilding the northern atolls of the Chagos Archipelago.

Dr Casey Benkwitt (Lancaster University) – How Rats Influence Coral Reefs

Casey is a marine ecologist who is broadly interested in the behavioural, population, and community ecology of reef fishes, with a focus on how human activities influence these processes. Originally from New Jersey, USA, she earned her B.A. in Environmental Studies and Sociology from Bowdoin College in Maine. While at university, Casey learned to scuba dive, which convinced her of two things – she wanted to conduct marine research and she wanted to do so in warmer waters. After spending a few years as a Fisheries Biologist and then a Marine Science Instructor, Casey earned her PhD in Zoology at Oregon State University studying how invasive lionfish affect native coral-reef fishes in the Caribbean. Casey then worked as a postdoctoral researcher at California State University, Northridge, where she researched the effects of different fishing regimes on sex-changing fishes in kelp forests. Casey is now a postdoc at Lancaster University as part of the Bertarelli Programme in Marine Science. Her current research focuses on how nutrient subsidies from seabirds influence coral reefs, including whether seabird-derived nutrients can boost the resilience of coral-reef communities to climate change and whether management actions to remove invasive rats and restore seabird populations benefit coral reefs.

If you’re interested in joining, please register online here.

Sentinel Species Research

Remarkable increase in turtle numbers on uninhabited islands

Dr Nicole Esteban and Dr Jeanne A. Mortimer authored a new study that reveals a massive increase in the number of turtles nesting on the Chagos Archipelago in the British Indian Ocean Territory, one of the world’s largest Marine Protected Areas (MPAs).

The British Indian Ocean Territory (BIOT), a British overseas territory that is located in the Indian Ocean about halfway between Tanzania and Indonesia, spans 640,000 km² and tops the list of global marine no-take areas. The Territory has some of the most biodiverse waters on the planet with over 220 species of coral, 855 species of fish and 355 species of molluscs swimming through its water. BIOT also contains the Chagos Archipelago, a group of seven atolls comprising more than 60 individual tropical islands.

Dr Esteban, your study revealed an increase of between 225% and 525% from 1996 to today for the critically endangered hawksbill turtle, and between 465% and 930% for the endangered green turtle. Were you expecting these results?

There haven’t been any detailed studies of the numbers of turtles besides the very baseline figures that we had from 1970, 1996 and 2006. We didn’t actually expect the number of turtles to have increased as much as they did. We were quite surprised.

What do you think the results mean for the conservation of these turtle species?

It’s fantastic news. In terms of conservation efforts, hawksbills are one of the most endangered species of marine turtles; they’re critically endangered on the IUCN Red List.

The British Indian Ocean Territory is a nesting refuge for a large proportion of the turtles nesting in the Western Indian Ocean – up to 51% of all hawksbills nest there. The fact that there’s such a large proportion nesting on uninhabited islands, well-protected by the MPA, is a really good for their conservation.

Do you think that this success is because of the MPA?

I think we have to be a little bit cautious because the MPA has only been formally in existence for just under ten years, and it takes 30-40 years to be able to document the recovery of sea turtle numbers. However, exploitation of turtles has been prohibited in the Territory since the 1970s so we can certainly attribute the recovery of sea turtle numbers in the British Indian Ocean Territory to long-term sea turtle conservation and protection. Laws were introduced in the early 1970s that protected turtles in the Chagos Archipelago and I would expect that this recovery will continue with the additional protection provided by the MPA.

One of the ways that you documented turtle activity was by counting turtle tracks. But how did you know that a single turtle didn’t make multiple tracks?

In fact, each turtle does make multiple tracks, and one of the assumptions that we made was to estimate how many tracks each turtle makes before laying eggs. Typically a turtle emerges from the ocean multiple times and may dig several trial nests before actually laying a clutch of eggs. This is because she may encounter obstacles on the beach or sand that is too soft or too hard before she is finally able to lay eggs. In our data analysis we’ve made the assumption of an average of 1.8 tracks for every egg clutch laid. This is based largely on data from turtles in Seychelles which are genetically related to those in the Chagos Archipelago and utilise very similar nesting habitats.

The other thing to bear in mind is that it’s really difficult to go to a remote island and count the number of tracks because much of the beach gets washed clean every spring tide. Therefore much of the data collected, especially in the remote outer islands, was based on counts of “body pits” high up on the beach platform. Body pits are the depressions turtles leave on the beach when they dig nests. These body pits can last for weeks or months, so they’re a much more reliable source of information.

How did you get involved with the Bertarelli Foundation, the funders of this study?

The Bertarelli Foundation started a marine science programme which involved a number of projects carried out in the British Indian Ocean Territory. Our team applied for a grant to fund key research relating to hawksbill and green turtles breeding and foraging across the five islanded atolls of the Chagos Archipelago.

Were there any other unexpected discoveries?

At the time we began our study, seagrass meadows (the favourite food of green turtles) were believed to be relatively rare in the Chagos Archipelago. We anticipated that most of the green turtles that nested in the archipelago would migrate to foraging sites elsewhere in the Western Indian Ocean. Thanks to funding from the Bertarelli Foundation, however, we’ve discovered that after nesting in the MPA some of the satellite-tracked green turtles remain within the archipelago and forage on the Great Chagos Bank, the largest living coral atoll in the world. With the help of these satellite-tracked turtles we were able to discover large areas of deep water and previously unknown seagrass meadows in the MPA.

What comes next?

We still have many things to learn about the ecology of sea turtles in the Chagos Archipelago. We would like to do more surveys of nesting activity in the remote uninhabited islands of the archipelago. We need to try to reduce the assumptions that we’re using to calculate total number of turtles nesting.

We also want to learn more about the survival rates of egg clutches and the hatching turtles they produce, so that’s another area of enquiry. We’ve started looking at the effects of temperature on incubation and how beach litter affects the success of turtle nesting. We’re also starting to test different technologies to enhance the ability to monitor remotely.

There’s lots to find out!

This research was published in Oryx and was supported by the Bertarelli Foundation.

Mortimer, J. A., Esteban, N., Guzman, A. N. and Hays, G. C. (2020) “Estimates of marine turtle nesting populations in the south-west Indian Ocean indicate the importance of the Chagos Archipelago,” Oryx. Cambridge University Press, pp. 1–12. DOI: 10.1017/S0030605319001108.

Coral Reefs

The Heat is on for the Survival of Chagos Archipelago’s Coral Reefs

Original post:

Back-to-back heatwaves kill more than two-thirds of coral.

The heat is on for the survival of the Chagos Archipelago's coral reefs.

ZSL scientists have shown the devastating effects of back-to-back heatwaves in the region surrounding the Chagos Archipelago. Coral cover was reduced by 60% in 2016 and by a further 30% in 2017. Nonetheless, this also indicates that some coral species have a higher resilience to rising temperatures thus offering some hope for the future.

Although representing les than 1% of our marine habitats coral reefs harbour a quarter of marine life. There are strong economic, conservation and scientific reasons for us to safeguard these reefs in a changing world.

In 2015 an eight weeklong heatwave struck the Chagos Archipelago, causing the seawater of the area to be unusually hot for a prolonged period. Researchers compared surveys of the reef before and after the heatwave in order to map the changes and harm it caused to the reefs. Evidence from 2015’s observations shows a 60% reduction in coral cover in the MPA. This included a dramatic 86% decline in the branching Acropora species that was previously a dominant reef building coral.

A year later, and before any recovery was possible, this region was subject to another bleaching event caused by a four-month long heatwave. Using data from Peros Banhos atoll an estimated 68% of the remaining corals had bleached. This suggest that around 70% of the reef area covered by corals was lost between 2015/2017.

Although more severe than the first heatwave, the second did less damage than the previous one. The first one killed corals most vulnerable to heat stress, leaving the more resilient colonies to try and survive the second. The fact that a few species have a higher heat tolerance is a glimmer of hope. According to Dr. Catherine Head the increasing severity and occurrence of heatwaves will inhibit shallow reefs ability to regenerate from bleaching events. It previously took 10 years for coral reefs to regenerate in BIOT, there is a high probability that the more vulnerable coral species will completely die off in the near future if these bleaching events become more frequent.

Preliminary reports from 2019 suggest a grim future for the Indian Ocean Region’s reefs as another heatwave was recorded and observations made of the start of yet another bleaching event of unknown impact. Research is key to understanding how corals adapt to rising sea surface temperatures and how we can positively impact their recovery.

Sentinel Species Research

Guano Versus El Niño

Original post:

How Bird Poop May Save Coral Reefs.

Warming sea surface temperatures have destructive effects on coral reefs, as shown during the 2015-2016 El Niño global bleaching event.

Corals rely on a highly important symbiotic relationship with an algae, called zooxanthellae. When sea temperature rises these algae can become toxic to the coral and are thus expelled, causing the coral to loose its color and appear “bleached”. Nonetheless, corals can eventually recover from bleaching events in the right circumstances and if given enough time.

Nitrogen and phosphorus occur naturally at very low levels on coral reefs, making them a notoriously nutrient-poor environment. These elements are key to the photosynthesis of the plants and algae on which coral reef ecosystems rely and act as limiting factors. To the surprise of researchers in BIOT, it seems that seabird’s guano (rich in nutrients) can provide an essential “boost” triggering coral recovery.

Indeed, seabirds are known to defecate frequently and most of this guano ends up in coral reefs ecosystems (directly or indirectly). A recent study states that this nutrient enhancement is critical for corals after a bleaching event.

The same study investigated on the coral saving guano by looking at ten islands. They found that reefs surrounding islands with a substantial seabird population had a greater growth of calcareous algae This particular seaweed serves as glue for reefs to form a barrier and is an indicator of a healthy ecosystem. Therefore, scientists suggest that guano provides optimal nitrogen to phosphorus ratios essential to reefs recovery and that we can’t replicate. Moreover, reefs surrounding healthy populations of seabirds experienced a healthier and more resilient fish population than reef with no birds.

“There is no example that is as clear cut and effective in enhancing the functioning of coral reefs in the face of climate change.”

Improving MPA Management

UN: Overfishing and Climate Change are Main Threats to Marine Biodiversity

Original post:

UN report: Ocean biodiversity in peril due to overfishing and climate change.

Human activities have significantly altered the marine environment by two-thirds, and climate change has made the situation worse.

A recent UN report paints a devastating picture of the world’s flora and fauna in terrestrial and marine environments. Indeed, the biodiversity of the world’s oceans is declining in a way unparalleled in human history. The Inter-State Science-Policy Platform for Biodiversity Ecosystem Services (IPBES) report has been written by about 150 expert authors from 50 different countries assessing global change to the health of our ecosystems over the past five decades. Only the opening summary of the report has been published so far. The full report is expected to exceed 1,500 pages and will be released later this year.

“The health of the ecosystems we and all other organisms depend on is deteriorating faster than ever before,” IPBES President Sir Robert Watson said in a statement. “We are eroding our economies, livelihoods, food security, health and the quality of life around the world.”

According to the report, climate change is an additional threat, and depending on humanity’s efforts to prevent warming, fish biomass may drop to 3-25% of current levels by the end of the century. 90% of the world’s fishers, more than 30 million people, are engaged in subsistence fishing which represents about 50% of the world’s total fishing effort.

“The ocean is facing many and various threats, and climate change and plastic pollution are getting a lot of media attention,” said Angelo O’Connor Villagomez, a senior officer at the Pew Bertarelli Marine Heritage Project. “The United Nations Report on Biodiversity reminds us,” I quote: “Direct exploitation of organisms, mainly fishing, has had the greatest negative relative impact on nature since the 1970s.”

Villagomez said he believes the fully protected marine sanctuaries are crucial to protection of marine biodiversity. About 15% of the world’s oceans are under some form of protection. In recent years, conservation efforts have resulted in the rapid spread of marine protected areas and other forms of spatial protection. Still, the International Union for Conservation of Nature recommends protecting 30% of every marine habitat to ensure the sustainability of our oceans.

These spatial prototypes have been shown to work for coastal and non-migratory species such as scallops, lobsters and reef fishes, but their impact on large migratory species such as tuna and billfishes is less evident, says Kristina Boerder, a postdoctoral fellow at Dalhousie University in Halifax, Canada

A new study by Boerder suggests that carefully designed and managed MPAs can benefit large migratory species. These ocean sanctuaries have helped rebuild the already heavily exploited fish stocks, according to Kristina, but the success of these MPAs depends on the context of each fisheries. MPAs are particularly useful when englobing known migratory routes or in “hot-spots” where various marine species aggregate to either breed, feed, or for other reasons. A better understanding of the behavior and motions of highly migratory species would enable fisheries to adjust spatial protection to species’ needs.

“We already have a lot of data and knowledge on areas such as those with significant spawning or where different species tend to congregate, but the political will to protect these areas is often absent” – Kristina Boerder

To ensure that protected areas are not just lines on a map where IUU and unsustainable fishing can operate unchecked, we need MPA managers to be equipped with the human capacity and necessary technology to carry out more efficient monitoring and management of the MPA. Well managed protected areas, fisheries and marine habitats will increase reefs resilience to climate change and may be beneficial to local fishermen, who rely on the oceans resources for economic and food security

Improving MPA Management

Research is Essential to Maximise Benefits of Marine Protected Areas

Original post:

Research Key to Boosting Benefits of Large Marine Protected Areas.

Even though a lot of preparation and scientific investigation is required for the creation of marine protected areas (MPAs), even the most skilled marine scientists have limited knowledge of these remote areas.

The reason for this lack of knowledge is because previous marine conservation efforts have been focused on the minor coastal MPAs which were created before the more remote offshore MPAs, and are easier to study, monitor and protect due to their location and size. Coastal research findings can be extrapolated to offshore MPAs; however, it does not give a complete view of exactly what is happening in these regions. We can achieve such an understanding by increasing research efforts and communication, which would then inform governments and conservationists as to how to deliver meaningful ecological outcomes for these MPAs. Achieving this understanding requires extensive research and reporting and should help governments, scientists and conservationists design and implement large MPAs with strong environmental outcomes.

To identify gaps in research on large MPAs, the Pew Bertarelli Ocean Legacy project collaborated with fisheries scientists Chris Smith and Quentin Hanich of the University of Wollongong, Australia. They co-authored a paper, Large Scale Marine Protected Areas: Current status and consideration of socio-economic dimensions, summarizing the research needed to inform the management and design of large MPAs. It examines protected areas from multiple perspectives and addresses concerns from stakeholders and governments in developed and developing states. There is a broad number of areas where research could improve our MPAs, mainly in regard to migratory routes, Illegal Unregulated Unreported fisheries, climate change, traditional cultures and indigenous communities.

For example, the Papahanamukukia National Marine Monument in the Northwest Hawaii Islands was one of the first major marine protected areas in the world but was closed for commercial fishing only recently (2011). Moreover, there has been no follow up investigation into the economic or environmental impacts of this closure, its effects are unknown to stakeholders or the government. With the increasing creation of MPAs worldwide, it becomes necessary for research to be addressing such gaps to understand how large MPAs benefit both the ecosystem and its surrounding communities. The Ocean Legacy project aims to fill these gaps by working tightly with nonprofit organizations, universities and scientists. The Bertarelli Foundation’s Program in Marine Science (BPMS) is already filling these gaps with its research in the British Indian Ocean Territory.

The U.N Convention on Biological Diversity will meet in the coming year to set new global goals for the protection of global biodiversity. The UN aims to protect 10% of our oceans by 2020. With the deadline approaching, there is a chance for the UN to realign its goal with the more realistic recommendation of the IUCN for 30% of our oceans to be protected in a network of MPA by 2030. The establishment of such a network requires the implementation of many small to large MPA’s protecting all types of marine habitats and creating protected corridors along migratory routes. As stated in a landmark study “without adequate protection of species and ecosystems outside reserves, effectiveness of reserves will be severely compromised”. There is a need to look at our MPAs & fisheries as part of a whole in order to increase the sustainability of our oceans, worldwide. Habitats where marine life spawns, forages and breeds must be accordingly protected and managed with the best science and infrastructure available.

Improving MPA Management

Using Reef Sharks as an Anti-Poaching Force

Original post:

Something smells fishy: Scientists uncover illegal fishing using shark tracking devices.

Source paper: https://marine-science-cms.dev.bflexion.technology/publication/potential-detection-of-illegal-fishing-by-passive-acoustic-telemetry/?

Sharks can now take a stand against illegal fishing as marine ecologists discover that their telemetry data can inform on the presence of illegal fishing fleets.

About 95 silvertip and grey reef sharks have been acoustically tagged to measure how effective the British Indian Ocean Territory (BIOT) Marine Protected Area (MPA) is at protecting them.

A recent study shows that the synchronous loss of 15 acoustic tags in BIOT concurs with two illegal fishing ships being arrested for having 359 sharks on deck. Although its primary use was to map sharks’ movements around the reef, the acoustic tag’s data can now be used to inform on the presence of illegal fishing vessels. In spring of 2015, scientists returned to BIOT to service their acoustic receivers surrounding the archipelago, and to download the tag data from their 95 tagged sharks. To their surprise, in ten days 15 of these 95 sharks disappeared, presumably lost to illegal fishing.

Marine conservationists are increasingly using acoustic telemetry as a way to collect data from species. Scientists from Stanford University Hopkins Marine Station, ZSL and University of Western Australia have collaborated using such technology to track reef shark movement around the MPA since 2013. Acoustic tags emit a unique sound received by hydrophones which then enables their localisation. Accuracy is not optimal, locations pinpointed can still be hundreds of metres away which is why such technology (acoustic telemetry) is mostly used on more resident species than highly mobile ones.

During 2013 and 2014 and after a lengthy developmental phase and ethical review, the team tagged 47 grey reef sharks (Carcharhinus amblyrhynchos) and 48 silvertip sharks (Carcharhinus albimarginatus). These sharks were tagged and released in the BIOT MPA. The aim of this release is to track shark movements. The transmitters are usually placed on the shark’s dorsal fin. They allow a fine scale mapping of their habitat as they remain highly loyal to their reef and therefore, remain within range of the receivers. The sudden disappearance of 15 sharks is not common and most likely represents a successful illegal fishing operation.

Sharks have been particularly targeted in the last decade in BIOT and around the world. 90% of illegal fishing ship encountered in BIOT had sharks on board, making up most of the catch. This coincides with a global trend where sharks have been targeted worldwide to fuel the demand in fin soup which has now gown in popularity over Asia and is becoming cheaper and more accessible.

The team studying sharks in BIOT during spring of 2015 decided to investigate the possible relationship between illegal fishing events and the disappearance of their tags. They found that, statistically, less than 50 tags were enough to detect such illegal events and could therefore be used to detect poaching events. Nonetheless, improvements in technology are still needed, there is a need for the data from tags to be collected quicker for a more effective intervention from the BIOT Patrol vessel. In the meantime, the team on location is teaching enforcement officers where and when sharks aggregate using the data that already exists combined with historical fisheries.

“Using animals as sentinels, both to detect illegal activity and to monitor environmental conditions, extends our capabilities and reach, making us more effective stewards of our oceans.”

D. M. Tickler

Coral Reefs

The Impact of Black Rats on Coral Reefs

Original post:

The Impact of Rats on the Health of Coral Reefs

The British Indian Ocean Territory includes the Chagos Archipelago and 58 small islands. Some of which are home to black rats (Rattus rattus), while others luckily remained rat-free.

Researchers in the Bertarelli Programme in Marine Science studied both islands, with and without rats, to see what effect the presence of rodents has on the health of the surrounding coral reefs.

The presence of back rats on islands in BIOT results from human exploration of our seas. Many islands around the world have been completely taken over by black rats that we accidentally introduced through ships years ago. Upon arrival on these seabirds-filled islands rats began to eat their eggs, chicks and even full-grown adults. This had disastrous consequences on native seabird populations on these invaded islands, 90% of tropical islands saw their bird population crash.

Thankfully, a small number of islands were spared and could act as a haven for the remaining frigate birds, boobies, terns and shearwaters. In BIOT, 18 of the 58 islands remained rat free.

Professor Nick Graham commented: “The rat-less islands are full of noisy birds, the sky is full, and the smell is strong – because of the bird’s guano deposits on the island. If you visit an island with rats, there is almost no seabirds. “

On rat-free islands, seabirds, including boobies, frigate birds, noddies, shearwaters and terns, roam for hundreds of miles to feed out in the open ocean. Upon their return to the island, they deposit rich nutrients from the fish they eat. These nutrients then spread into the surrounding waters and affected the biology of reef systems.

The results, published in Nature, are clear: the fish on reefs adjacent to the rat-less islands grew faster and bigger than that of the fish living in islands infested by rats.

Therefore, rat-filled islands have an indirect impact on the already fragile reef, since seabirds provide nutrient rich guano to the surrounding reef.

Since coral reefs are constantly affected by changes in ocean temperature and with coral bleaching frequency increasing, this research suggests that the elimination of invasive species such as rodents could be an important way to increase the resilience of these critical habitats while also restoring native populations of seabirds.

To date 500 islands have been gradually de-ratted and, according to Dr. Graham, 2-3M$ is necessary to fully de-rat BIOT.