Last week the Reef Ecology and Restoration team completed the March monitoring surveys of the 5 year reef study around the patches of Eleuthera. The March surveys usually call for thick wetsuit, hoods and hot chocolate. However, the water was particularly warm at 27oC, resulting in the surveys being completed in record time. Dr Jocelyn Curtis-Quick has been leading this study since 2012; she now plans to use this incredibly unique and invaluable dataset to thoroughly examine the influences and impacts that the invasive lionfish have on the patch reef ecosystem.
Every part of the reef is searched for lionfish
The Reef Ecology team has already begun the process of analysis, and Jocelyn was able to present some of these preliminary findings at the Bahamas Natural History Conference in Nassau earlier in the month. By continuing to spread and enhance the local knowledge within Eleuthera and beyond, the management of the lionfish will hopefully continue to grow.
Removing lionfish from the reef
Of the 16 patches that have been surveyed throughout the study, 8 have been designated as removal sites, and with a highly experienced team we were able to continue our contribution to the culling effort around The Bahamas and wider Caribbean. Stay tuned to hear the full results of our study and a more detailed picture of how the lionfish is making its presence felt around Southern Eleuthera. In the mean time don’t forget, You Slay, We Pay!
Dr. Jocelyn Curtis-Quick and her team have been assisting Dr. Heather Masonjones with her ongoing seahorse research in Sweetings Pond. Sweetings Pond on the island of Eleuthera contains a diverse array of species, including both seahorses and octopuses. Originally described in the early 1980’s, this pond has remained unstudied over the past 30 years.
The amazing seahorses of the pond (photo credit Shane Gross)
This type of tidal saltwater pond forms in regions with limestone geologic histories, fed from the ocean through cracks and underground caverns. Depending on the size of these connections and how long they have been isolated from gene-flow, these ponds are well known sites of speciation, with an array of endemic or limited-range organisms, and unfortunately, a long list of species declines. The Sweetings Pond site is part of wider assessment of the inland ponds found all over Eleuthera, led by Dr. Jocelyn Curtis-Quick.
All seahorses found are photographes as their marking can be used to identify individuals
Seahorses are marine fish that have captivated humans for generations. Worldwide, their populations are under threat from over-harvesting for curios, traditional medicines and as bycatch from fisheries. They are also declining because of decreasing water quality of their shallow coastal habitats, and increased use of these habitats through poorly-managed tourism. The impacts of these threats are difficult to measure in seahorses, because they are difficult to study in the wild. The pond species of seahorses, Hippocampus erectus, is also listed as Vulnerable on the IUCN Red List, an international organization dedicated to conservation.
At night a black light shows the tagged fish (photo credit Shane Gross)Lili Wagner finds a baby octopus on the light trap
The team spent two days assessing the seahorse’s use of different habitats and successfully tagged more than 30 seahorses, enabling the mark and recapture technique to be used to assess population density. In order to assess what the seahorses are eating, as there is little to no research on their prey selection at night, the team set out plankton tows and executed gastric lavage procedures on the seahorses. The stomach contents were preserved and will be sent to a lab at the University of Tampa to be analyzed, and the animals were released unharmed back to the exact location where they were originally found. Because of their monogamous mating system, moving animals from their home location can interrupt mating pairs, and make it difficult for animals to reproduce.
Populations of seahorses are rarely as dense as we have measured in the pond, so from a conservation perspective, this would be an excellent choice of location to protect and conserve for future generations. Dr. Masonjones presented the preliminary findings at the Bahamas Natural History Conference last week.
If you see seashores in the water around Eleuthera please report your sightings on iSeahorse.
The Reef Ecology and Restoration team welcomed Prof. Mary Wicksten to CEI last week. Prof. Wicksten is a professor at Texas A&M University, College Station, where she works on the biogeography, systematics and behavior of decapod crustaceans. Prof. Wicksten is collaborating with CEI’s Dr Jocelyn Curtis-Quick on the anchialine pond research.
Rare shrim found in the ponds of Eleuthera. Photo credit: Drew Hitchner
During Prof. Wicksten’s visit, she got to explore some of the inland ponds and helped to identify deep sea crab species for other researchers at the institute. Prof. Wicksten used her expert ID skills to also identify crabs and shrimp present in the stomach contents of some lionfish. Prof. Wicksten had the opportunity to talk with the young ones from the ELC about crustaceans – inspiring future scientists!
Although a short visit to the CEI, Prof. Wicksten made the most of her time, and even helped to support the ongoing lionfish outreach. She attended the Blue Seahorse art show, where the Reef Ecology team was increasing lionfish awareness, particularly the importance of removing the lionfish from the reefs and spreading the word that it is a really good fish to eat!
It was a pleasure to have Prof. Wicksten with us for four amazing days!
High on top of the Bahamian crest is a queen conch—an iconic representation of how truly integrated marine ecosystems are to Caribbean culture. Queen conch (Strombus gigas) is a large gastropod native to the Caribbean and has been a staple in the Bahamian diet for centuries. Unfortunately, the overfishing of conch has caused massive declines in populations, and conservation efforts are greatly needed to promote a healthy and sustainable conch fishery in the Bahamas.
Selecting conch at random to be used in a trial
In fisherman lore around the Bahamas it is said to be bad luck to throw knocked conch into the water, as it will scare away living conch—thus, huge conch middens are often found onshore. But, some conch are still tossed overboard at sea, and it is thought this may also be affecting conch populations. The Sustainable Fisheries team, here at the Cape Eleuthera Institute (CEI), is testing avoidance behavior from conch with help of several Island School students. The main question is- do conch flee upon seeing/smelling an injured or dead conspecific, and if so, what sort of cue is triggering movement?
Sustainable Fisheries intern Cara measures the distance moved by a conch in a behavioral trial
So far 40 trials have been conducted, and CEI’s Claire Thomas, Program Manager for Sustainable Fisheries, will be presenting the preliminary results at the Bahamas National Trust Natural History Conference in Nassau this week. As we conduct more trials and gain more insight into potential conch avoidance behavior, there may be implications for new management strategies to better protect this important species—stay tuned for results!
Captain and mate of team Shady Lady weigh in a wahoo. When dissected at CEI’s lab, this fish was found to have a ingested a piece of plastic.
This February, the Cape Eleuthera Institute partnered with Davis Harbor Marina and the Cotton Bay Club for the inaugural Davis Harbour Wahoo Rally. The two day fishing tournament allowed Davis Harbour Marina and anglers to contribute to ongoing research at CEI, making the Wahoo Rally as scientifically valuable as it was fun for the participating teams.
This partnership, and the enthusiasm of Davis Harbour Marina and the fishing teams, highlights CEI’s commitment to including anglers in ongoing research initiatives.
CEI researchers including (from L to R) a MSc student, a CEI intern, and a PhD student assisted with the collection of tissue samples
Continue reading to learn more about the angler-driven projects that were contributed to during the Wahoo Rally.
The team take measurements of a stingray prior to fitting an iButton
In the past week, members of the Stingray Research Team from the Shark Research and Conservation Program (SRCP) have begun work on a new project investigating the thermal ecology of southern stingrays (Dasyatis americana). As part of the research for this new study, the stingray team, assisted by gap year students and interns, fitted southern stingrays with temperature recorders. These recorders monitor seawater temperatures experienced by stingrays every 15 minutes for 3 weeks.
Southern stingray fitted with iButton swims away after release
All sharks and rays are ectotherms, meaning their internal body temperature is controlled by the temperature of the environment around them. As such, changes in seawater temperature can impact the physiological processes of the animals, which may mean that temperature differences among the coastal waters of Eleuthera influence the areas which rays use.
Surgical needles are used to make holes in the stingrays tail in order to attach the iButton
Over the next 4 months, the study aims to tag 50 rays at both Marker Bar and the Schooner Cays, as well as conduct laboratory experiments with rays to identify thermal preferences. Also, temperature tags fitted to wild individuals will aid in understanding whether temperature is a driver of habitat selection in this ray species. Quantifying the drivers for habitat use of these ecologically important species is vital to effectively manage coastal marine habitats. The research is led by Daniel Montgomery, a postgraduate research student at Newcastle University, who is working in collaboration with Dr. Owen O’Shea and CEI.
Four members of the Cape Eleuthera Institute (CEI) community, including members of the Shark Research and Conservation Program (SRCP) and the reef ecology team, ventured down to Hummingbird Cay in the Exumas to further Dr. Owen O’Shea’s study on the elusive Caribbean whiptail stingray (Himantura schmardae). Very little is known about this species, but it is vital to elucidate information pertaining to their biology and ecology in order to calculate effective conservation methods. The main goal of this project is to determine connectivity and gene flow of the Caribbean whiptail stingray by collecting tissue samples from individuals across multiple spatial scales.
The stingray team with a large male whiptail ray at Hummingbird Cay
Stingrays are one of the most influential architects to their ecosystems, as they impact their surroundings in numerous ways. They hold an integral position in coastal food webs, acting as predators to animals in lower parts of the food chain and prey to those higher up, such as sharks. Their physical movements involve bioturbation – meaning reworking and suspending of sediments. This oxygenates the sediment around them and re-suspends nutrients, promoting primary productivity. Although there are gaps in our understanding regarding the behavioral tendencies of the Caribbean whiptail stingray, they are likely significant agents within their ecosystems.
The expedition began with four extremely successful days in the field; with near perfect weather conditions, the team caught 13 rays over a spatial scale exceeding 35 miles – something critical when evaluating gene flow of a species. Nine of these were male and all rays ranged from 80cm disc width to around 140 cm with all estimated as being mature or sub adult – an inverse trend in the population sampled from south Eleuthera.
Day five offered a frustrating morning without a single ray observed due to strong northerly winds, churning up the fine sediments, seemingly synonymous with this species. However, it wasn’t long before the team moved on to the leeward side of one of the islands and stumbled across an aggregation of 17 whiptail rays. The group consisted of very large adult stingrays, most of which were resting or casually mobile and seemed unflustered when we slipped quietly into the water for a closer inspection. Until now, no records exist in the literature of aggregations in this species from The Bahamas, and we can only speculate about how common this type of aggregation may be for this species. What is certain is that it was an honor to witness such a substantial group of these huge animals.
Between last year’s expedition and this most recent trip, DNA and stable isotope information has been collected from 15 individuals from this location and 23 from Eleuthera. This study will continue to grow as samples are expected to be collected over a larger spacial scale in the months to come, filling in the gaps from the rest of the Exuma chain.
We would like to acknowledge the Rufford Foundation for funding this work and making this expedition possible. Also, thank you to the exceptional team at Hummingbird Cay for welcoming us so hospitably and for helping to make our trip so successful.
Nassau grouper is an economically important species in The Bahamas. Due to heavy fishing pressure, there have been marked decreases in their population sizes, especially noticeable during their spawning season. The spawning season takes place during the winter months, from December to the end of February, and the aggregations occur during the full moon. Dr. Kristine Stump from the Shedd Aquarium has been monitoring Nassau grouper in The Bahamas to track their movements to spawning aggregations, as well as to quantify the number of Nassau grouper at these historical spawning sites.
The researchers that took part in the Nassau grouper work in front of the Shedd Aquarium vessel
This January, the Shedd Aquarium research vessel, The Coral Reef II, travelled to Long Island, to historical spawning sites, with a representative of The Cape Eleuthera Institute on board, to assist Dr. Stump with her research. Throughout the week-long journey, the researchers on board performed dive surveys to quantify spawning stock size at one specific site. Unfortunately, very few Nassau grouper were aggregating at the site during the times of the surveys; at most 20 were noted on one survey. Illegal fishing was occurring at the time the vessel reached the site, which could explain the decreased abundance of the grouper. Poor weather conditions prevented the researchers from performing surveys on the night of the full moon, so it is unclear if numbers increased during the spawning event. Continue reading →
Christian McIntosh presenting at the Abaco Science Alliance Conference
Christian McIntosh, a BESS scholar and a Fall 15 Inland Ponds Research Class student, recently presented the group’s work at the Abaco Science Alliance Conference. This conference is a biannual event hosted by Friends of the Environment, where Christian is currently interning. The conference invites scientists to present their work and findings to fellow scientists, as well as the local community and school groups. Christian talked with passion about the unique life he found in the ponds of Eleuthera during his research class.
Andrieka Burrows at work collecting data on inland ponds
Exciting news just in – last week Andrieka Burrows, fellow BESS scholar and Fall 15 Island School student, had her abstract accepted to present more ponds research at the Bahamas Natural History Conference this March. The goal of the conference is to inspire new avenues of research and cooperation across disciplines while highlighting the benefits of research of the environment, economy and human society of The Bahamas. We are sure Andrieka will do an excellent job and create more interest and support for the conservation of these understudied and fragile systems.
We are very proud of our young scientists, Christian and Andrieka, and hope this is the start of not only the protection of anchialine systems, but the beginning of long careers in the conservation of The Bahamas’ natural resources.
Island School students in the field assessing a pond and the life within
Students cleaning off the seine net after a long day’s work
Recently, St. Thomas Aquinas High School from Dover, New Hampshire helped conduct research with the CEI sea turtle research team in Winding Bay. Although the weather was uncooperative on Friday while the group was seining, they came out strong with the capture of five green sea turtles in their first attempt. Seining is a method used by several research teams at CEI that involves a very long net that temporarily encloses the animals inside.
The group on Saturday had to put in a little more effort as it took five seining attempts to finally capture three green sea turtles!
Students take the curved carapace length (CCL) of one of the turtles
One turtle that was captured, Kyra, had its left rear flipper almost completely detached. The wound was healed and the flipper still had some movement. What caused the damage is unknown, but Kyra is lucky to have kept this limb! Green turtles don’t typically use their rear flippers much except for maneuvering while swimming, and females use them for digging a nest.
A turtle being measured
Both groups had the opportunity to experience the challenge it is to catch sea turtles and keep them steady to take measurements! It was all worth it as one student said, “This was the best day so far!”
by 
