Christy Pattengill-Semmens

• Ph.D. Biology
• Reef Environmental Education Foundation (REEF)

The scalloped hammerhead shark (Sphyrna lewini), a critically endangered species with a decreasing global population, is characterised by its occurrence in large schools. Such schools are still observed today in the Pacific Ocean, but this is generally not the case in the Atlantic Ocean, and in the Cayman Islands not since the 1970s. Here we report...

The state of biodiversity for most of the world is largely enigmatic due to a lack of long‐term population monitoring data. Citizen science programs could substantially contribute to resolving this data crisis, but there are noted concerns on whether methods can overcome the biases and imprecision inherent to aggregated opportunistic observations....

Dispersal of eggs and larvae from spawning sites is critical to the population dynamics and conservation of marine fishes. For overfished species like critically endangered Nassau grouper (Epinephelus striatus), recovery depends on the fate of eggs spawned at the few remaining aggregation sites. Biophysical models can predict larval dispersal, yet...

Tiger Grouper (Mycteroperca tigris) form fish spawning aggregations (FSAs) around the winter full moons (typically January through April) in the Caribbean. Males defend territories to attract mates in a lek-like reproductive strategy. Prior studies have documented rapid declines in populations with FSA-associated fisheries. This study examines the...

Four species of grouper (family Epinephlidae), Red Hind ( Epinephelus guttatus), Nassau ( Epinephelus striatus), Black ( Mycteroperca bonaci), and Yellowfin Grouper ( Mycteroperca venenosa) share an aggregation site in Little Cayman, Cayman Islands and produce sounds while aggregating. Continuous observation of these aggregations is challenging bec...

Long-term monitoring enables scientists and managers to track changes in the temporal and spatial distributions of fishes. Given the anthropogenic stressors affecting marine ecosystem health, there is a critical need for robust, comprehensive fish monitoring programs. Citizen science can serve as a meaningful, cost-effective strategy to survey fish...

No PDF available ABSTRACT Red hind ( Epinephelus guttatus) and Nassau (E. striatus), black (Mycteroperca bonaci), and yellowfin grouper (M. venenosa) form spawning aggregations in Little Cayman, Cayman Islands and produce sound during these aggregations. Continuous observation of these aggregations is challenging because traditional methods are lim...

Fish spawning aggregations (FSAs) are vulnerable to overexploitation, yet quantitative assessments of FSA populations are rare. We document an approach for how to conduct such an assessment, evaluating the response of Critically Endangered Nassau Grouper (Epinephelus striatus) to protections in the Cayman Islands. We assessed pre-protection status...

Characterizing the behavior of coral reef fishes at home reef sites can provide insight into the mechanisms of spatial ecology and provide a framework for spatial resource management. In the Caribbean, populations of Nassau grouper Epinephelus striatus have declined due to fishing impacts on spawning aggregations. Despite local and regional efforts...

Many large-bodied marine fishes that form spawning aggregations, such as the Nassau grouper ( Epinephelus striatus ), have suffered regional overfishing due to exploitation during spawning. In response, marine resource managers in many locations have established marine protected areas or seasonal closures to recover these overfished stocks. The cha...

Multihost infectious disease outbreaks have endangered wildlife, causing extinction of frogs and endemic birds, and widespread declines of bats, corals, and abalone. Since 2013, a sea star wasting disease has affected >20 sea star species from Mexico to Alaska. The common, predatory sunflower star ( Pycnopodia helianthoides ), shown to be highly su...

Since the onset of fisheries science, monitoring programs have been implemented to support stock assessments and fisheries management. Here, we take inventory of the monitoring programs of the U.S. Gulf of Mexico (GOM) surveying fish and invertebrates and conduct a gap analysis of these programs. We also compile a large monitoring database encompas...

Many fish species are known to produce stereotyped calls during spawning activities. It has been hypothesized that these calls play a vital role in coordination during this critical period. Competition for acoustic space can result in masking of calls and, as a result, may limit their function. Acoustic niche separation could be a solution to avoid...

Sea star wasting disease devastated intertidal sea star populations from Mexico to Alaska between 2013–15, but little detail is known about its impacts to subtidal species. We assessed the impacts of sea star wasting disease in the Salish Sea, a Canadian / United States transboundary marine ecosystem, and world-wide hotspot for temperate asteroid s...

Code for the multilevel Poisson regression. (DOCX)

Species and basin specific ARIMA models and their estimated parameter values. (DOCX)

Managing natural populations and communities requires detailed information regarding demographic processes at large spatial and temporal scales. This combination is challenging for both traditional scientific surveys, which often operate at localized scales, and recent citizen science designs, which often provide data with few auxiliary information...

I will present an in situ visual mark-resighting study design that can be used to estimate total abundance of spawners at an aggregation site. I demonstrate the methods using recent findings from the Grouper Moon program, a collaborative research program between Reef Environmental Education Foundation (REEF), Cayman Islands Department of Environmen...

Biogeochemical hot moments occur when a temporary increase in availability of one or more limiting reactants results in elevated rates of biogeochemical reactions. Many marine fish form transient spawning aggregations, temporarily increasing their local abundance and thus nutrients supplied via excretion at the aggregation site. In this way, nutrie...

A database of fish surveys conducted by volunteer recreational divers trained by Reef Environmental Education Foundation (REEF) was used to examine fish populations in Monterey Peninsula, California, between 1997 and 2011. Over 3,000 surveys were conducted as part of this ongoing citizen science effort. Variations in relative density over time are...

We describe several models to convert order-of-magnitude count data to a numeric mean and demonstrate that with a sufficient number of surveys, estimates of the mean with a reasonably small confidence interval can be attained. The method is applied to fish survey data collected as part of the Reef Environmental Education Foundation (REEF) Volunteer...

Background/Question/Methods Biogeographic and temporal patterns in community assembly can provide insights regarding the processes driving rocky reef fish diversity in the Salish Sea. However, relatively few sets of broadly distributed observations on marine fish assemblages exist in Salish Sea. The Reef Environmental Education Foundation (REEF)...

Assessing population trends, evaluating management actions, and identifying community responses to anthropogenic impacts all require an accurate time series of populations. In practice, such data are often scarce or of varying quality due to the limited resources of managing agencies. In such situations, analyses that integrating multiple data sour...

Recent concerns about changing elasmobranch populations have prompted the need to understand their patterns of distribution and abundance through non-destructive sampling methods. Since scientific divers represent a small portion of the total number of divers worldwide, the use of non-scientific divers could drastically increase the number of obser...

Nassau grouper Epinephelus striatus are a large bodied, top level predator that is ecologically important throughout the Caribbean. Although typically solitary, Nassau grouper form large annual spawning aggregations at predictable times in spe-cific locations. In 2003, The Cayman Islands Marine Conservation Board established protection for a newly...

Assessing population trends, evaluating management actions, and identifying community responses to anthropogenic impacts all require an accurate time-series of populations. In practice, such data are often scarce or of varying quality due to the limited resources of managing agencies. In such situations, analyses that integrating multiple data sour...

In recent decades, large pelagic and coastal shark populations have declined dramatically with increased fishing; however, the status of sharks in other systems such as coral reefs remains largely unassessed despite a long history of exploitation. Here we explore the contemporary distribution and sighting frequency of sharks on reefs in the greater...

Mass spawning aggregations of Caribbean grouper species are a conservation priority because of declines due to over-fishing. Previous studies have documented five historical aggregation sites in the Cayman Islands. Today, three of these sites are inactive or commercially extinct. In January 2002, the Reef Environmental Education Foundation led an e...

Invasions of non-native species in marine ecosystems can be ecologically damaging and economically costly. Identifying ‘hot-spots’ of non-native species and their sources of introduction is necessary to maximize the effectiveness of invasion quarantine programs. We use a large spatially explicit marine fish database to show that there are a surpris...

The REEF Fish Survey Project is a volunteer fish monitoring program developed by the Reef Environmental Education Foundation (REEF). REEF volunteers collect fish distribution and abundance data using a standardized visual method during regular diving and snorkeling activities. Survey data are recorded on preprinted data sheets that are returned to...

The Atlantic and Gulf Rapid Reef Assessment (AGRRA) fish survey was conducted in depths of 3-14 m at 22 coral reef sites in the U.S. Virgin Islands (St. Croix, St. John, St. Thomas) and the British Virgin Islands (Anegada, Guana Island, Virgin Gorda). Total fish species richness, determined by using the roving diver technique was 72-160 species. A...

The fish assemblages at 33 sites around the islands of Grand Cayman and Little Cayman were assessed in June 1999 for the Atlantic and Gulf Rapid Reef Assessment initiative using belt transects and Roving Diver Technique surveys. A comprehensive species list, with 58 new records, was compiled for the Cayman Islands based on these data and survey dat...

The REEF/TNC Fish Survey Project is a volunteer fish monitoring program developed by the Reef Environmental Education Foundation (REEF) with support from The Nature Conservancy (TNC). REEF volunteers collect fish distribution and log scale abundance data for the project using a standardized visual method. These data are housed in a publicly accessi...

Using non-experts in monitoring programs increases the data available for use in resource management. Both scientists and resource managers have expressed concerns about the value and accuracy of non-expert data. We examined the quality of fish census data generated by Reef Environmental Education Foundation (REEF) volunteers of varying experience...

Using nonexpert volunteers in monitoring programs increases the data available for use in resource management. Both scientists and resource managers have expressed concerns about the value and accuracy of nonexpert data. We examined the quality of fish census data generated by Reef Environmental Education Foundation (REEF) volunteers of varying exp...

Nassau grouper (Epinephelus striatus) migrate to specific sites during the winter full moons in order to reproduce in mass aggregations. The Nassau grouper is listed as endangered by the International Union for Conservation of Nature and Natural Resources (IUCN). Intense harvesting of spawning aggregations is the primary cause of the precipitous de...

Coral reefs are subject to major anthropogenic impacts worldwide and sites in decline are prime candidates for management and restoration. In assessing trends, it is imperative to have data from a wide area, over several years, and for many species. We assessed trends in 50 common coral reef fishes at 21 sites throughout the Florida Keys National M...

Nassau grouper (Epinephelus striatus) were historically one of the most important shallow water fisheries in the Caribbean, yet now are rarely taken. Although normally solitary, during the winter full moon Nassau grouper attend aggregations at spawning site to reproduce. Now, however, there are only a handful of known Nassau grouper aggregations wi...