As part of the Grouper Moon Project in Little Cayman, Cayman Island, this study used the sound produced by Nassau Grouper, Red Hind, Black Grouper, and Yellowfin Grouper to monitor the positions of these fish during the Nassau grouper spawning event that occurred in 2017. By using fish sound recorded by multiple instruments, we were able to monitor the presence and location of these fish before, during, and after the spawning. These continuous and overnight records added valuable observations to the limited period of times when divers are able to survey the area. Knowing the locations of the fish, it was possible to measure how loud these fish sounds are and determine how far they may be detected. The authors found that Nassau Grouper sounds were the loudest and may be detectable up to 300 m at this location. Additionally, the timing and locations of sound production suggest that there is no Nassau spawning events that occur during the night, but there may be overlap in space and time between Red Hind and Nassau Grouper spawning aggregations.
2022
REEF was one of five citizen science (CS) project teams that participated in a multi-year study funded by the National Science Foundation to understand CS volunteers’ accuracy and skills. This paper is the culmination of that study, which included several facilitated exercises and meetings between external researchers and the project participants. The CS teams identified a wide range of skill variables that were “hiding in plain sight” in their data records that could be explored as part of a secondary analysis. Each team identified a small number of evaluation questions to explore with their existing data. REEF's "hiding in plain sight" was using surveys collected in different scenarios (solo surveyor, surveying with a buddy, surveying in a group during a REEF Trip) to evaluate skill gains as measured by the number of species reported on each survey. The results from these analyses were then used to inform the design of both existing and new CS projects, and to inform the field more broadly through a range of dissemination strategies.
First sighted in Lebanon in 2012, invasive lionfish have since become well-established in the Mediterranean Sea. In an effort to provide policy recommendations for the lionfish invasion within the Mediterranean Sea, REEF joined in a global collaborative effort with researchers from Europe, Asia, Africa, North America, and the Caribbean to share successes and failures from two decades of lionfish management in the Western Atlantic. As a result of this work, a paper titled "Lessons from the Western Atlantic lionfish invasion to inform management in the Mediterranean” was recently published in the journal Frontiers in Marine Science.
Invasive lionfish control will require rapid and strategic management approaches, multinational coordination and broad cooperation among and between governments and stakeholders. The infographic (above) accompanying this article details some of the recommended and failed approached for lionfish management. Lessons for invasive lionfish management identified in the paper include:
• Conducting routine removals by spearfishing with scuba can effectively suppress local abundances of lionfish
• Encouraging the development of recreational and commercial lionfish fisheries can facilitate sustainable lionfish population control
• Engaging local communities can help achieve lionfish removals, market-development, research, and public education.
The authors also advised against failed approaches such as feeding lionfish to native fish to promote predation and implementing bounty programs to incentivize lionfish harvest. A detailed table of lionfish management strategies in both the Western Atlantic and Mediterranean was compiled by REEF staff to support the article and can be found here.
2021
East Pacific Green Sea Turtles (Chelonia mydas) have undergone substantial population recovery over the last two decades because of comprehensive protection at nesting beaches and foraging areas. Starting in 2014 in southern California (United States), at the northern end of their range, Green Sea Turtles have been seen in more areas and in greater numbers. A resident population of Green Sea Turtles has established near La Jolla Shores (off San Diego Country), a protected site with daily marine tourism (e.g., kayakers, snorkelers, divers). The REEF Volunteer Fish Survey Project, a global citizen science marine life monitoring program, has included sea turtle sightings since 2001. The REEF dataset from San Diego, CA, was used as one of several sources of information to study this local population of sea turtles. This paper summarizes the authors' findings. The study is the first to look at the apparent behaviors and condition of Green Sea Turtles observed in the La Jolla Shores area and the first to provide information about Green Sea Turtle distribution throughout southern California based on opportunistic sightings by the general public.
The impacts of invasive lionfish (Pterois volitans/miles) on native coral reef populations in the Western Atlantic Ocean and Caribbean Sea can be enormous. However, how much lionfish differ from native predators and whether their effects outweigh the abundant mesopredators that occupy many reefs invite continued examination. The authors of this paper present empirical evidence from Caribbean Panama and beyond, suggesting that lionfish are less abundant than native mesopredators (e.g. small seabass). In addition, their findings show that direct impacts by lionfish and Graysby, a native mesopredator, on survivorship and size distributions of one native prey species (Masked Goby) are similar. The authors used REEF data collected from sites throughout the Caribbean, Gulf of Mexico, and Western Atlantic from 2010-2015 to test whether lionfish were less common than Graysby. By leveraging the citizen-science dataset collected by REEF volunteers, the authors were able to evaluate the impacts of native and non-native mesopredators across a much broader geographic region and longer time period than otherwise possible based solely on surveys conducted as part of their field work, which were limited to just one year in Caribbean Panama. REEF data substantially enhanced the evidence used to show that lionfish tended to be much less common than Graysby over the 6-year period. The findings of this paper will help guide lionfish management and control, and provides support for synergies between conservation actions aimed both at the invasion and other consequential problems such as overexploitation and climate change.
Designing effective local management for invasive species poses a major challenge for conservation, yet factors affecting intervention success and efficiency are rarely evaluated and incorporated into practice. As part of a multi-year study with funding from NOAA Coral Reef Conservation Program and others, REEF and partners coordinated regional efforts by divers to cull invasive lionfish (Pterois spp.) on 33 U.S. Atlantic, Gulf of Mexico, and Caribbean protected coral reefs from 2013 to 2019. During each effort, the researchers estimated removal efficiency and efficacy as a function of environmental and habitat conditions, invasion status, and personnel expertise. Highly experienced individuals culling during crepuscular periods (2 hr from sunrise/sunset) are three times more efficient (in terms of minutes) than novice divers during midday, suggesting: (a) retention of experienced individuals is key for efficient programs, and (b) planning culls with personnel and time of day in mind increases the number of sites covered with the same effort. Lionfish behavior and habitat characteristics had little effect on removal efficiency and efficacy, but divers had higher capture success at reefs with higher lionfish densities. The authors suggest reefs with persistently low densities of lionfish be given low priority for management efforts, given that impacts to native fauna are unlikely and culling effectiveness declines to <50% below this level. Incorporating efficiency factors in spatial management planning along with estimates of lionfish density can help ensure that limited resources for control are extended across a greater range of invaded habitats.
Fish usually need to be caught to be measured, but scientists from the Grouper Moon Project and Cayman Islands government have used video camera systems to collect an impressive 17-year dataset of Nassau Grouper lengths from Little Cayman. We combined this with information on growth and abundance to produce a comprehensive assessment of Nassau Grouper on Little Cayman. We found that Nassau Grouper recovered on Little Cayman largely thanks to one strong year class from 2011 spawning, 4-8x average. Length data from Cayman Brac also showed signs of a strong 2011 year class and substantial improvement in population status in recent years. Our analysis demonstrates that video camera systems are effective for monitoring protected fish spawning aggregations and are especially promising for situations where catch, effort, and invasive length data are unavailable.
With 15,000 tube feet and up to 24 arms, the magnificent Sunflower Sea Star (Pycnopodia helianthoides) is found from Baja Mexico to Alaska. Since 2013, this magnificent species has suffered a dramatic decline due to a wasting disease. Many fear that the species may be on the brink of extinction. To quantify the decline and possibly establish grounds for protections and intervention, REEF joined in a partnership of more than 60 institutions led by The Nature Conservancy and Oregon State University. REEF provided data collected through the Volunteer Fish Survey Project to help establish whether the Sunflower Sea Star warranted listing on the International Union for Conservation of Nature (IUCN)’s Red List of Threatened Species. REEF shared data from 32,517 REEF surveys conducted at hundreds of sites between California and Alaska from 1998 to 2019, which included 18,035 records of the Sunflower Sea Star. Thanks to the efforts of our volunteer surveyors, REEF was able to contribute almost a third of the data used in the IUCN assessment.
The analysis found a 90.6% decline in the species. The resulting report was issued to the IUCN in fall 2020 and in December of that year, it was announced that the Sunflower Sea Star was placed on the IUCN Red List as Critically Endangered, just one step below extinction. The decline has had cascading impacts on the marine environment. Sunflower Sea Stars are a main predator of sea urchins, whose populations have now exploded in many regions. Higher numbers of sea urchins, which feast on kelp, has led to “urchin barrens” and a significant decline in kelp forest ecosystems.
This paper evaluates population trends in Giant Pacific Octopus (GPO) in the Pacific Northwest using REEF Volunteer Fish Survey Project data and other data sources. The authors found large changes in GPO abundance linked to average water temperatures. GPO sighting frequencies ranged from a high of 39% to a low of 11%. For every additional degree increase of 4-year average temperatures, the Puget Sound GPO sighting frequency dropped about 19 points. That’s a loss of roughly 75% of typical diver sightings for every degree C. The authors also noted that, of the many datasets they used to conduct the analysis (including a transect study in Prince William Sound focused on GPO), the REEF dataset provided the most comprehensive set of information on GPO populations and provided the strongest correlation coefficients.
Managing invasive Indo-Pacific lionfish (Pterois volitans and P. miles) in the Western Atlantic Ocean is beyond the capacity of natural resource organizations alone. In response, organizations have mobilized members of the public and citizen scientists to help. The authors used a structured survey to assess the activities and perceptions of 71 organizations that engage the public and citizen scientists in lionfish research and management throughout the invaded range of the Western Atlantic. REEF's work as part of our Invasive Species Program is one of five case studies included in the paper. The case studies highlight the varied and multi-pronged approaches to engagement of the public and citizen scientists in lionfish control, monitoring, and knowledge-sharing.
Since 2006, REEF has been working in close partnership with government agencies and partners throughout the region to help develop lionfish response plans, train resource managers and dive operators in effective collecting and handling techniques and conduct cutting edge research to help address the invasion.