Predator–Prey Interactions Examined Using Lionfish Spine Puncture Performance

Synopsis Puncture mechanics can be studied in the context of predator–prey interactions and provide bioinspiration for puncture tools and puncture-resistant materials. Lionfish have a passive puncture system where venomous spines (dorsal, anal, and pelvic), the tool, may embed into a predator’s skin, the target material, during an encounter. To examine predator–prey interactions, we quantified the puncture performance of red lionfish, Pterois volitans, spines in buccal skin from two potential predators and porcine skin, a biological model for human skin. We punctured dorsal, anal, and pelvic lionfish spines into three regions of buccal skin from the black grouper (Mycteroperca bonaci) and the blacktip shark (Carcharhinus limbatus), and we examined spine macro-damage (visible without a microscope) post puncture. Lionfish spines were more effective, based on lower forces measured and less damage incurred, at puncturing buccal skin of groupers compared to sharks. Anal and dorsal spines incurred the most macro-damage during successful fish skin puncture trials, while pelvic spines did not incur any macro-damage. Lionfish spines were not damaged during porcine skin testing. Anal spines required the highest forces, while pelvic spines required intermediate forces to puncture fish skin. Dorsal spines required the lowest forces to puncture fish skins, but often incurred macro-damage of bent tips. All spine regions required similar forces to puncture porcine skin. These data suggest that lionfish spines may be more effective at puncturing humans such as divers than potential fish predators. These results emphasize that puncture performance is ultimately determined by both the puncture tool and target material choice. Lionfish puncture performance varies among spine region, when taking into account both the puncture force and damage sustained by the spine.

Marine ornamental trade in Indonesia

Trade with marine species as ornamentals is an important sector of the international pet trade. The vast majority of these species are collected from the wild and one of the top supplying countries is Indonesia. Detailed evidence on trade with marine resources in Indonesia is lacking or it is hardly accessible. Moreover, the exploitation of ornamental species seems to be mostly uncontrolled. This study presents detailed characteristics of such trade for Indonesia, including the offered species, their sizes, prices, and conservation status, based on data and information obtained from wholesalers in 2018. The main provinces of marine wildlife collecting are also identified. In total, 777 marine vertebrate and invertebrate species were traded, belonging to 174 families including two species classified as endangered: Banggai cardinal fish (Pterapogon kauderni) and zebra shark (Stegostoma fasciatum). Commonly traded was red lionfish (Pterois volitans), known to be a successful invader. The volume of ornamental marine fish exported from Indonesia in period 2015–2019 was 3 353 983 kgs sold for 33 123 218 USD. The province of Bali was identified as the main exporter of ornamental marine fish within Indonesia. These findings should help to establish sustainable exploitation of marine resources in relation to conservation and wildlife management.

Initial sightings and derby data from the red lionfish invasion (Pterois volitans) (Scorpaeniformes: Scorpaenidae) in Barbados

Native to the Indo-Pacific region, the lionfish (Pterois volitans and P. miles) has been classified as an alien invasive species which has rapidly invaded the North-western Atlantic and the Caribbean. The primary concerns regarding lionfish pertain to their broad diet, general habitat use and their potential threat on fisheries resources, native fish communities and human health. Away from natural predators, lionfish populations can easily become established and pose a serious threat to local fish species and ecosystem functioning. The first confirmed sighting of the red lionfish (Pterois volitans) in Barbados was in November 2011. Throughout 2012, fishermen and recreational divers were encouraged to report sightings of lionfish via an established hotline. Where possible, sightings were confirmed by way of the fish being captured and handed over to the Barbados Fisheries Division or the East Coast Conservation Organisation (ECCO) Inc. (an environmental NGO) for confirmation. In addition to confirmation, biological data (such as length, weight, sex and maturity) were also collected. Genetic research conducted on confirmed specimens collected between 2011-2013 identified the presence of only one species, P. volitans. Since the first confirmed sighting of the red lionfish in Barbados, it is believed that population numbers have steadily increased. One of the methods utilised in Barbados to control this alien invasive lionfish species is that of an annual derby. On 5 and 6 December 2015 and 13 November 2016, teams of divers (both free divers and SCUBA divers) took to the local waters to hunt for and kill lionfish. Caught lionfish were landed at scoring stations to be counted and allowed for the collection of basic biological data (such as length, weight, sex and maturity). In addition to biological data, teams (observers) also provided information on dive sites (locations) and associated geographic information (i.e. GPS coordinates), where available. These two datasets, initial sightings (2012) and derby data (2015 and 2016), present the first collected data for the red lionfish (P. volitans) in Barbados. The two datasets are occurrence datasets which document the identification of >1500 lionfish removed from the waters of Barbados between 2011 and 2016.