Fishermen Interviews: A Cost-Effective Tool for Evaluating the Impact of Fisheries on Vulnerable Sea Turtles in Tunisia and Identifying Levers of Mitigation

Fisheries bycatch is considered one of the main threats to sea turtles. To provide an updated assessment of the bycatch impact on loggerhead turtles in Tunisia, 483 interviews were conducted with fishermen in 19 ports along the Gulfs of Gabes and Hammamet. The interview questions included data on vessel and fishing gear characteristics, monthly fishing effort, and monthly sea turtle bycatch of the last year. Results revealed that sea turtle bycatch per unit effort (BPUE) was the highest for ray nets (0.73 turtles/vessel/day, 95% CI [0.02-1.15]), followed by pelagic longlines (0.6 turtles/vessel/day, 95% CI [0-4.23]) and shark nets (0.4 turtles/vessel/day, 95% CI [0-2.12]). However, due to the trawlers' high fishing effort, the cumulative impact of the trawl nets was the highest with an estimated number of 11,740 (95% CI [0-41,525.75]) turtles caught per year in Tunisia. Factors influencing the bycatch risk were gear characteristics (mesh size for nets, hook size for longlines, vertical opening for trawls), as well as season and location of operations. These factors will guide the research of mitigation solutions. The interviews with fishermen proved to be a cost-effective approach for the rapid assessment of sea turtle interactions with fisheries in the context of Tunisia.

Characterization of the complete chloroplast genome of Firmiana hainanensis (Malvaceae), an endemic and vulnerable tree species of China

Firmiana hainanensis Kosterm. is a commercially valuable endemic tree species in China and has long been considered a globally vulnerable species. We assembled and characterized the complete chloroplast genome of this species by using Illumina pair-end sequencing data. The total chloroplast genome size was 161,559 bp, including two inverted repeats (IRs) of 25,612 bp, separated by a large single copy (LSC) and a small single copy (SSC) regions of 90,057 and 20,277 bp, respectively. A total of 130 genes were identified, including 85 protein-coding genes, 37 tRNA, and eight rRNA genes. Phylogenetic analysis showed that F. hainanensis was the most basal species in the genus Firmiana. The chloroplast genome of this species will provide a theoretical basis to understand the taxa's evolution further and is expected to contribute to its conservation efforts.

Characterization of the complete chloroplast genome of Trailliaedoxa gracilis (Rubiaceae)

Trailliaedoxa gracilis (Rubiaceae) is a Chinese endemic monotypic genus distributed in southwestern China. This study reported the complete chloroplast genome of T. gracilis assembled from Illumina sequencing reads. The chloroplast genome size is 152,407 bp, containing a single large copy (LSC) region of 82,957 bp, a short single copy (SSC) region of 17,936 bp, and a pair of inverted repeats (IRs) of 25,757 bp. A total of 127 genes were found, including 82 protein-coding genes, 37 tRNA genes, and eight rRNA genes. A phylogenetic analysis using the maximum likelihood algorithm revealed that T. gracilis belonged to the subfamily Ixoroideae and had the closest relationship with Scyphiphora hydrophyllacea.

Demography of the black grouper, Mycteroperca bonaci (Poey, 1860) (Teleostei: Epinephelidae) from the North Brazil Shelf

Mycteroperca bonaci (black grouper) is one of the most sought species of grouper along its entire distribution, being a prime target for demersal line fisheries because of its high commercial value. Nonetheless, because of population declines the species is considered near threatened according to the IUCN red list. The present study aimed to determine the population parameters of M. bonaci, including growth, reproduction and mortality, and thus contributes to measures towards its conservation and management in the southwestern Atlantic. The sampling area is in the North Brazil Shelf, off Maranhão State, an area of intense fisheries development and yet poorly known. The large continental shelf harbours unique coral reef formations and has been declared an ecologically or biologically significant marine area (EBSA). Sampling on landing sites was carried out monthly between May 2017 and January 2019. A total of 137 black grouper specimens were sampled from commercial landings of artisanal fisheries. The size of the specimens ranged from 44 to 157 cm, and the weight varied from 0.976 to 54 kg. The length-weight was established: log(TW) = -11.26 + 3.01log(TL). Histological analysis of the gonads confirmed only the presence of female individuals, and the occurrence of individuals in the sexual transition was not recorded. Higher GSI values and higher frequency of spawning capable staged individuals occurred during the months of June to August, indicating spawning peaks. The estimated age of sexual maturity A50 for females was 4.62 years ( x _ 93 cm-TL). The growth parameters for the Von Bertalanffy model were TL∞ (cm): 185.5, k: 0.04, t₀ (year): -4.75 (t₀ not fixed) and TL∞ (cm): 141, k: 0.11 (t₀  = 0 fixed). The total estimated mortality rate (Z) according to catch length presented a Z value = 0.11, and the natural mortality was M = 0.04 year^-1 . This is the first study on the age and growth of M. bonaci in the SWA, a region where the species is considered as endangered according to Brazil's red list regional assessment. Only females were present in the samples, results that suggest either differential capturability of sexes because of distinct patterns of behaviour or distribution or an effect of selective mortality upon larger and older individuals, as the species is described as a protogynous hermaphrodite. This indicates the need to closely manage this population to avoid collapses. Recovery plans that have been planned by the Brazilian government but not yet implemented for the species must be put into practice to avoid progressive decline as fisheries target more remote areas.

An estimate of the number of white sharks Carcharodon carcharias interacting with ecotourism in Guadalupe Island

The aim of the present study is to provide an estimate of the number of white sharks Carcharodon carcharias that seasonally interact with ecotourism boats in Guadalupe Island using Schnabel's mark-recapture method and 6316 records of white sharks during 2012-2014. The results of the estimation highlight an abundance of 78 white sharks 95% C.I. (62.1, 105.6) interacting with ecotourism. The regulations regarding the number of tourists, boats and the monitoring of white sharks should be assessed to improve management decisions regarding the conservation and sustainable use of this threatened species.

Development of SSR markers for Astragalus lehmannianus, a vulnerable species from northwestern China

PREMISE

Astragalus lehmannianus (Fabaceae) is a vulnerable species found in the cold deserts of northwestern China. We aimed to characterize polymorphic microsatellite loci for A. lehmannianus to support future studies of population genetic dynamics and conservation management of the species.

METHODS AND RESULTS

We used next-generation sequencing to detect polymorphic microsatellites. Twenty-five potential microsatellite loci were identified, 12 of which were polymorphic and present in the three study populations of A. lehmannianus. Levels of observed and expected heterozygosities were 0.000-1.000 and 0.000-0.827, respectively. Furthermore, two and five of the 12 developed primers were successfully amplified in two congeneric species, A. arpilobus and A. oxyglottis, respectively.

CONCLUSIONS

These newly developed microsatellite markers can be used to determine population diversity and to develop conservation strategies in A. lehmannianus.

The complete chloroplast genome sequence of a vulnerable legume species Dalbergia tonkinensis prain in Vietnam

Dalbergia tonkinensis is a critically vulnerable tree species that is distributed in Vietnam and Hainan Island of China. The complete chloroplast genome sequence of D. tonkinensis was characterized using Illumina pair-end sequencing. The cpDNA is 156,086 bp in length and contains a pair of 25,720 bp inverted repeats, one large single copy region of 85,761 bp, and one small single copy region of 18,885 bp. It contains 131 genes including 86 protein-coding genes, 36 tRNAs, eight rRNAs, and one pseudogene. The overall G + C content of the whole genome is 36.1%. Phylogenetic analysis based on 35 chloroplast genomes of Papilionoideae including Cercis glabra (as an outgroup) indicates that all the species of the Dalbergioids sensu lato formed a monophyletic clade and D. tonkinensis formed a sister relationship with the D. hainanensis and D. odorifera group.

Testicular volume and semen characteristics in the endangered southern muriqui (Brachyteles arachnoides)

BACKGROUND

The southern muriqui (Brachyteles arachnoides) is an endangered Neotropical primate. Semen collection and description of its traits, as well as testicular morphometry, have never been reported for this species.

METHODS

Testicles from five healthy adult captive southern muriqui were measured, and semen was collected by rectal probe electrostimulation (RPE).

RESULTS AND CONCLUSIONS

A solid coagulum was identified in all ejaculates, and none of them liquefied, spontaneously or non-spontaneously. It was possible to collect semen using RPE, and although solids coagula did not liquefy, we managed to describe ejaculates characteristics and also confirmed that southern muriqui have relatively large testes size. Further investigations are needed to improve coagulum handling, to achieve a better spermatozoa recovery aiming its application in assisted reproductive technologies.

Nothodissotis (Melastomataceae), a new genus from Atlantic Central Africa, including the new species N.alenensis from Equatorial Guinea

Based on morphological and phylogenetic evidence, a new genus of Melastomataceae (Melastomateae), Nothodissotis Veranso-Libalah & G.Kadereit, gen. nov., is described from Atlantic Central Africa. Nothodissotis is distinguished from other African Melastomateae genera by its calyx-lobes that are notched at apex and asymmetrical (vs. entire and symmetrical). Nothodissotis includes two species: the type species N.barteri (Hook.f.) Veranso-Libalah & G.Kadereit, comb. nov. (syn. Dissotisbarteri Hook.f.), and the new species N.alenensis Veranso-Libalah & O. Lachenaud, sp. nov., described and illustrated here. Both species are restricted to open vegetation on rock outcrops within the forested region of Atlantic Central Africa. Nothodissotisbarteri has a scattered distribution in Cameroon, Equatorial Guinea, Gabon and Príncipe Island, while N.alenensis is endemic to the Monte Alén massif in Equatorial Guinea, an area where N.barteri does not occur. Nothodissotisalenensis differs from N.barteri by its hypanthium bearing sessile appendages with penicillate hairs (vs. stalked stellate appendages) and its staminal appendages that are much smaller in antepetalous than in antesepalous stamens (vs. subequal in all stamens). The conservation status of both N.barteri and N.alenensis is assessed as Vulnerable in accordance with IUCN criteria.

The complete chloroplast genome sequence of Saussurea polylepis (Asteraceae), a vulnerable endemic species of Korea

The complete chloroplast genome sequence of Saussurea polylepis, one of vulnerable and endemic species of Korea, was determined. The genome size was 152,488 bp in length with 37.7% GC content. It included a pair of inverted repeats (IRa and IRb) of 25,191 bp, which were separated by small single copy (SSC: 18,689 bp) and large single copy (LSC: 83,417 bp) regions. The cp genome contained 113 genes, including 80 protein-coding genes, 29 tRNA genes, and four rRNA genes. Phylogenetic analysis of the combined 80 protein coding genes and four rRNA genes showed that S. polylepis was closely related to S. chabyoungsanica.

Evaluating the effectiveness of teeth and dorsal fin spines for non-lethal age estimation of a tropical reef fish, coral trout Plectropomus leopardus

This study investigated whether teeth and dorsal fin spines could be used as non-lethal methods of age estimation for a vulnerable and highly valued tropical fisheries species, coral trout Plectropomus leopardus. Age estimation of individuals from 2 to 9 years old revealed that dorsal spines represent an accurate ageing method (90% agreement with otoliths) that was more precise [average per cent error (APE) = 4·1, coefficient of variation (c.v.) = 5·8%] than otoliths (APE = 6·2, c.v. = 8·7%). Of the three methods for age estimation (otoliths, dorsal spines and teeth), spines were the most time and cost efficient. An aquarium-based study also found that removing a dorsal spine or tooth did not affect survivorship or growth of P. leopardus. No annuli were visible in teeth despite taking transverse and longitudinal sections throughout the tooth and trialling several different laboratory methods. Although teeth may not be suitable for estimating age of P. leopardus, dorsal spines appear to be an acceptably accurate, precise and efficient method for non-lethal ageing of individuals from 2 to 9 years old in this tropical species.

Spawning activity of the Australian lungfish Neoceratodus forsteri in an impoundment

This study assessed the spawning activity of the threatened Australian lungfish Neoceratodus forsteri by measuring egg densities within the artificial habitat of a large impoundment (Lake Wivenhoe, Australia). Eggs were sampled (August to November 2009) from multiple locations across the impoundment, but occurred at highest densities in water shallower than 40 cm along shorelines with a dense cover of submerged terrestrial vegetation. The numbers of eggs declined over the study period and all samples were dominated by early developmental stages and high proportions of unviable eggs. The quality of the littoral spawning habitats declined over the study as flooded terrestrial grasses decomposed and filamentous algae coverage increased. Water temperatures at the spawning site exhibited extreme variations, ranging over 20·4° C in water shallower than 5 cm. Dissolved oxygen concentrations regularly declined to <1 mg l⁻¹ at 40 and 80 cm water depth. Spawning habitats utilised by N. forsteri within impoundments expose embryos to increased risk of desiccation or excessive submergence through water-level variations, and extremes in temperature and dissolved oxygen concentration that present numerous challenges for successful spawning and recruitment of N. forsteri in large impoundment environments.