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1.
J Fish Biol ; 101(3): 540-549, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35638311

ABSTRACT

The whale shark Rhincodon typus is a broadly distributed and highly mobile planktivorous shark species. The sharks form predictable aggregations in many areas, providing the opportunity for cost-effective scientific monitoring through divers and other marine resource users. Sightings of individuals outside of these aggregate zones elsewhere in their range are typically rare. We used a citizen science-based approach to shed light on occurrence and seasonality in the waters around Koh Tao, Thailand and neighbouring islands in the Gulf of Thailand. Although there is a paucity of quantitative data, anecdotal reports suggest substantial declines in sightings in the early 2000s. We identified a total of 178 individual whale sharks (from 249 sightings) between 2004 and 2019, with most of these (84%) from the 2015-2019 time period due to an increase in sighting reports facilitated by social media and direct marketing. Size estimates were reported for 102 of the sightings, with a range of 2-6 m and mean of 3.7 m overall. Sex was reported for 27% of sightings, with a 2:1 female-to-male ratio. Modified maximum likelihood methods suggest whale sharks are transient to Koh Tao and surrounding areas, with whale shark sightings following the regional monsoon cycle. One international resighting was obtained from Malaysian waters (~700 km away). Encouraging citizen science participation is particularly useful in data-poor regions like the Gulf of Thailand, despite limitations in size and sex estimation reliability, which can play an important complementary role in dedicated research programs.


Subject(s)
Citizen Science , Sharks , Animals , Ecosystem , Female , Humans , Male , Reproducibility of Results , Seasons , Thailand
2.
Mar Environ Res ; 172: 105505, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34717128

ABSTRACT

Concrete cubic frames and decommissioned steel naval vessels have been deployed in Thailand liberally to act as artificial substrates for coral restoration and marine recreation. We assessed recruitment at such substrate types at Koh Tao, Gulf of Thailand, and compared the community structure of scleractinian corals between artificial substrates and nearby natural reefs. Our results from a sample of 2677 recruits from nine sites highlighted significant differences in community structure between both reef types. Investigations of variables including time since deployment, distance from the natural reef, and seafloor depth revealed only the latter as a possible influencing factor. The diversity of recruits could not be explained by dynamics in coral spawning, and were found to represent groups with lower structural complexity. Our results suggest that coral community structure on artificial and natural reefs differs and supports distinct ecological and functional roles.


Subject(s)
Anthozoa , Animals , Coral Reefs , Thailand
3.
Zookeys ; 1042: 73-188, 2021.
Article in English | MEDLINE | ID: mdl-34163291

ABSTRACT

Improved access to field survey infrastructure throughout South-East Asia has allowed for a greater intensity of biodiversity surveys than ever before. The rocky bottoms and coral reef habitats across the region have been shown to support some of the highest sea slug biodiversity on the planet, with ever increasing records. During the past ten years, intensive SCUBA surveys have been carried out at Koh Tao, in the Gulf of Thailand, which have yielded remarkable findings in sea slug biology and ecology. In this work a brief history of sea slug biodiversity research from Thailand is covered and a complete inventory of sea slugs from Koh Tao, Gulf of Thailand is provided. This inventory is based on surveys from 2012 to 2020, with previously unreported findings since 2016. Habitat specificity and species-specific ecology are reported where available with a focused comparison of coral reef habitats and deeper soft-sediment habitats. The findings contribute 90 new species records for Thai waters (92 for the Gulf of Thailand) and report a remarkable consistency in the proportional diversity found to be exclusive to one habitat type or another. Additionally, taxonomic remarks are provided for species documented from Koh Tao that have not been discussed in past literature from Thailand, and a summary of previous records in the Indo-West Pacific is given.

4.
Zookeys ; 969: 85-121, 2020.
Article in English | MEDLINE | ID: mdl-33013168

ABSTRACT

Research in recent years have provided rapid advances in biogeographic and taxonomic documentation of sea slugs around the world. However, efforts are lacking in surveying most coastlines and habitats in South-East Asia. Recent studies from the Gulf of Thailand have indicated that a wealth of unexplored sea slug diversity and ecology may be gained from an investigation of soft sediment habitats beyond the reef slopes. Additionally, the waters of Koh Tao have been found to host regionally high levels of sea slug diversity with several species awaiting taxonomic clarification. In this work the initial findings of an expanded survey effort from the waters around Koh Tao are provided, with the identity of two soft sediment-associated sacoglossan species in the family Plakobranchidae being investigated. By integrating morphological and molecular analyses, the species Plakobranchus noctisstellatus sp. nov. and Elysia aowthai sp. nov. are described and species complexes surrounding Plakobranchus ocellatus van Hasselt, 1824 and Elysia japonica Eliot, 1913 are discussed. The topics of morphological variability and the cryptic species problem are also discussed.

5.
PLoS One ; 14(4): e0215063, 2019.
Article in English | MEDLINE | ID: mdl-31034493

ABSTRACT

Recent studies revealed that reef corals can eat large-sized pelagic and benthic animals in addition to small planktonic prey. As follow-up, we document natural ingestion of sea slugs by corals and investigate the role of sacoglossan sea slugs as possible prey items of scleractinian corals. Feeding trials were carried out using six sacoglossan species as prey, two each from the genera Costasiella, Elysia and Plakobranchus, and four free-living solitary corals (Danafungia scruposa, Fungia fungites, Pleuractis paumotensis and Heteropsammia cochlea) as predators. Trials were carried out under both in-situ and ex-situ conditions with the aim to observe ingestion and assess signs of prey consumption based on tissue loss of prey individuals over time. Significant differences were observed in both ingestion time and consumption state of prey between prey species, with three of them being ingested more rapidly and preferentially consumed over the others. Additionally, prey size was found to be a significant factor with larger prey (>12 mm) being ingested more slowly and rarely than smaller ones (<6 mm and 6-12 mm). Comparisons of consumption capability among predators showed no significant difference with all coral species showing similar preferences for prey species. While no specific mechanism of prey capture is proposed, we also document instances of kleptoparisitism and resuspension of prey items by wrasses. This study highlights the important distinction between opportunistic prey capture and true predation events.


Subject(s)
Anthozoa/physiology , Feeding Behavior , Food Preferences , Gastropoda/physiology , Predatory Behavior/physiology , Animals
7.
J Clin Anesth ; 54: 102-110, 2019 May.
Article in English | MEDLINE | ID: mdl-30415149

ABSTRACT

STUDY OBJECTIVE: The first aim of this study was to test whether a 7 item evaluation scale developed by our department's certified registered nurse anesthetists (CRNAs) was psychometrically reliable. The second aim was to test whether anesthesiologists' performance changed with their years of postgraduate experience. DESIGN, SETTING, MEASUREMENTS: Sixty-two University of Iowa CRNAs evaluated 81 anesthesiologists during one weekend. Anesthesiologists' scores were adjusted for CRNA rater leniency. Anesthesiologists' scores were tested for sensitivity to CRNA-anesthesiologist case-specific variables. Scores also were tested against anesthesiologists' years of postgraduate experience. The latter association was tested for sensitivity to case-specific variables, anesthesiologists' clinical supervision scores provided by residents, and anesthesiologist clinical assignment variables. MAIN RESULTS: The 7 items demonstrated a single-factor structure, allowing calculation of mean score over the 7 items. Individual anesthesiologist scores were reliable when scores were provided by at least 10 different CRNAs. Anesthesiologists' scores (mean 3.34 [SD 0.41]) were not affected by the interval since last CRNA-anesthesiologist interaction, number of interactions, or case-specific variables. There was a negative association between leniency-adjusted anesthesiologist scores and years of anesthesiologist postgraduate practice (coefficient -0.20 per decade, t = -19.39, P < 0.0001). The association remained robust when accounting for case-specific variables, resident clinical supervision scores, and overall clinical assignment variables. CONCLUSIONS: Anesthesiologists' operating room performance can be evaluated reliably by non-physician anesthesia providers (CRNAs). The evaluation process can be done reliably and validly using an assessment scale consisting of only a few (<10) items and with evaluations by only a few individuals (≥10 CRNA raters). There is no indication evaluations provided by CRNAs were significantly influenced by the interval between interaction and evaluation, number of interactions, or other case-specific variables. From CRNAs' perspectives, on average, as anesthesiologists gain experience, anesthesiologists' behaviors in the operating room change, providing CRNAs with less direct assistance in patient care.


Subject(s)
Anesthesiologists/statistics & numerical data , Clinical Competence/statistics & numerical data , Employee Performance Appraisal/statistics & numerical data , Nurse Anesthetists/psychology , Physician-Nurse Relations , Anesthesiologists/psychology , Employee Performance Appraisal/methods , Humans , Operating Rooms , Psychometrics , Time Factors
8.
Mar Environ Res ; 103: 56-65, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25460062

ABSTRACT

While coral reefs are increasingly threatened worldwide, they are also increasingly used for recreational activities. Given the environmental and socio-economic significance of coral reefs, understanding the links between human activities and coral health and evaluating the efficacy of marine protected areas (MPAs) as a management regime to prevent further deterioration are critically important. The aim of this study was to quantify indicators of coral health at sites inside and outside a newly rezoned MPA framework in the dive tourism hotspot of Koh Tao, Thailand. We found that patterns in the health and diversity of coral communities one year on did not reflect the protected status conferred by newly zoned MPAs, but instead reflected past history of recreational use around the island. Sites characterised as past high-use sites had lower mean percent cover of hard corals overall and of corals in the typically disease- and disturbance-susceptible family Acroporidae, but higher mean cover of species in the more weedy family Agariciidae. Past high use sites also had higher mean prevalence of infectious diseases and other indicators of compromised health. Sites within the newly established MPAs are currently subjected to higher levels of environmental and anthropogenic pressures, with sedimentation, algal overgrowth, feeding scars from Drupella snails, and breakage particularly prevalent compared to sites in non-MPA areas. Given the greater prevalence of these factors within protected sites, the capacity of the MPA framework to effectively prevent further deterioration of Koh Tao's reefs is unclear. Nevertheless, our study constitutes a strong baseline for future long-term evaluations of the potential of MPAs to maintain coral health and diversity on highly threatened reefs.


Subject(s)
Anthozoa/physiology , Biodiversity , Conservation of Natural Resources , Animals , Coral Reefs , Islands , Population Dynamics , Recreation , Thailand , Time Factors
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