My research aims to test the gut microbiota as an indicator of health status and key predictor of survival for the Juan Fernandez fur seal

What is this all about?

My research aims to develop a method for safely monitoring the health of the Juan Fernandez fur seal population, using this method to determine the impact of human and environmental pressures and to help predict survival.

More about these fluffy animals and their home!

The Juan Fernandez Archipelago is among the few oceanic archipelagos along the west coast of South America. Located west of the Chilean continental territory in the Pacific Ocean, It is composed mainly of three volcanic islands; Robinson Crusoe (The sailor castaway from Defoe's book), Alejandro Selkirk (The real sailor) and the tiny Santa Clara. This paradise was designated a National Park in 1935 by the Chilean government and is administered by Corporación Nacional Forestal (CONAF). It is also considered a Biosphere Reserve by UNESCO since 1977.

These islands are highly isolated and are home to animals and plants that exist nowhere else in the world such as the Juan Fernandez fur seal, an endemic Otarid from the Juan Fernandez Archipelago and the Desventuradas Islands, where they come ashore for the breeding season during December and February.

During the 18th and 19th century commercial sealers massively hunted the seals until they end up disappearing and thought extinct. It was not until almost 100 years later (1958) that a small population was rediscovered. So...They were gone, but now they are back.

Since 1978 they have been protected by Chilean legislation allowing an increase in their numbers, but according to the International Union for Conservation of Nature, the limited population size, narrow geographical range and the genetic bottleneck through which they have passed, make them vulnerable to catastrophic events and stress from causes like diseases outbreaks, oil spills, environmental regime shifts and prey decline. Therefore performing continuous surveillance is needed for conservation.

How?

We will collect faecal samples from Juan Fernandez fur seals inhabiting two separate islands, each exposed to a different level of environmental pressure. Collecting faecal samples is a non-invasive method that allows me to retrieve samples after the seals have moved away so that they are not stressed. Once we have collected enough, we will go back to the lab where advanced genetic techniques will be performed to obtain two kinds of information: The fur seal’s identity/characteristics and the types of micro-organisms or “microbiota” that live in the seal known as the “microbiome*”. Therefore, each sample will come with the donor's health report, why? We need to be able to differentiate a healthy microbiota from those that look a bit "odd".

To summarise, we are able to obtain all sorts of information from the faecal samples, some of which belongs to the seal we are sampling and other information from whatever micro-organisms inhabit the seal's gut.

*This link will take you to YouTube video I found that explains the basics behind the microbiome in a very friendly way. Please have look, it will only take you 5 mins.

https://youtu.be/5DTrENdWvvM?list=PLkInycqmzcu1oNsM1t2-gGkt8ib2_ZANr

How do you know what sample belongs to who?

If you think of your genetic material (DNA) as an address, your postcode will depend on the country, city, and street you live in and there is a house number that only match your house. When we sequence RNA/DNA, it is like getting the postcode so we can go to the "genetic" address book and look for the closest match.

¿Faeces, microbes, genetics, diseases and conservation?

To achieve better conservation strategies we need to look for new solutions at the macro and micro-ecological levels. Analyzing the microbiome is becoming an important tool to support conservation efforts. Through interactions, beneficial or detrimental, microbes have a profound impact on their host's health. The microbial communities are extremely dynamic, showing fluctuations by location, between and within individuals and by host species. The microbiome (together with the metagenome) offers a non-invasive approach to host's health, nutrition, distribution, genetics, habitat quality and diseases.

Sentinel species mirror an ecosystem's health. Species located high in the food chain, such as seals, are considered to be excellent indicators of the health or quality of their habitat. Emergence of infectious diseases in wildlife has increased in the last decades impacting wildlife populations. Some diseases can easily pass to other species causing outbreaks in a wide range of organisms including human. The unpredictability of these events makes surveillance crucial for early detection. The health of higher organisms is not only dependent on genetics and nutrition but is also tightly linked to the types of microbial species that colonize them, particularly in the intestine, a major reservoir of microbial colonizers. This community is acquired at birth and through lactation from the mother and later from the environment and is modified by a series of factors including age, sex, circadian changes and environmental fluctuations. The gastrointestinal microbiome is involved in nutritional digestion, synthesis of essential nutrients and helps to control the host’s metabolic activity. In places where the environmental conditions suffer major changes throughout the year, the gut microbiome composition changes rapidly in order to buffer the host during periods of food constraint. The gastrointestinal microbiome also has a significant role in host health, contributing to the maturation/modulation of immune system helping to prevent pathogen invasion.

Diseases are one of the main causes of death in marine mammals, important ecosystem sentinel species. Most previous studies link disease susceptibility/death to disruption of immune system integrity caused by stressors like food source depletion, environmental contamination, climate change, and habitat degradation leading to decreasing host population sizes and reduced host genetic diversity. What is interesting is that all of these stressors have been also identified by experimental science to cause dysbiosis (microbial imbalance) in the microbiome and thus the metagenome. We aim to perform pioneer research that will be crucial for understanding the metagenome in wildlife through the study of Juan Fernandez fur seals. For the first time we expect to characterize their microbiome, in conjunction with their genetic background and finally compare how the host and associated microorganism relationship changes with age, health status and habitat characteristics with the aim of gaining an understanding of the gradual shifts in the communities that may tip the host into disease and/or death. Understanding these links is essential to identifying populations at risk and making ecologically appropriate management decisions.

Summarizing

This project will provide new, fundamental information on the faecal microbiota in Juan Fernandez fur seal. Both, individual's and microbial genetic information will be correlated. Such a study has not been attempted to date, making the findings of this project of significant impact on our understanding of what is a 'healthy' faecal metagenome and maybe be able to predict what animals/colonies may be less likely to survive. Therefore, it will contribute to improved strategies for conservation management of wild populations exposed to different levels of human pressures and environmental conditions and understanding the prevalence of potential human pathogens in pinniped species and vice-versa. There is also the possibility of discovering new microorganisms/pathogens in these pinnipeds.

What do we need the money for?

All the money raised in this campaign will be ONLY used to cover the field work expenses, including sampling material, camping gear and travel costs.