Correcting for heterogeneous availability bias in surveys of long-diving marine turtles

AbstractPlastic pollution, and especially plastic ingestion by animals, is a serious global issue. This problem is well documented in marine systems, but it is relatively understudied in freshwater systems. For turtles, it is unknown how plastic ingestion compares between marine and non-marine species. We review the relevant turtle dietary literature, and find that plastic ingestion is reported for all 7 marine turtle species, but only 5 of 352 non-marine turtle species. In the last 10 years, despite marine turtles representing just 2% of all turtle species, almost 50% of relevant turtle dietary studies involved only marine turtles. These results suggest that the potential threat of plastic ingestion is poorly studied in non-marine turtles. We also examine plastic ingestion frequency in a freshwater turtle population, finding that 7.7% of 65 turtles had ingested plastic. However, plastic-resembling organic material would have inflated our frequency results up to 40% higher were it not for verification using Raman spectroscopy. Additionally, we showcase how non-native turtles can be used as a proxy for understanding the potential for plastic ingestion by co-occurring native turtles of conservation concern. We conclude with recommendations for how scientists studying non-marine turtles can improve the implementation, quality, and discoverability of plastic ingestion research.

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Between interpretation and the subject: Revisiting Bakhtin’s theory of polyphony

Semiotica ◽

10.1515/sem-2019-0086 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Jie Zhang ◽

Hongbing Yu

Keyword(s):

Literary Theory ◽

Global Field ◽

Availability Bias ◽

Obvious Consequence ◽

The Subject ◽

Influential Theory

AbstractThis paper affords a critical and historical reappraisal of Bakhtin’s theory of polyphony. It addresses the issue of the subjectivity of interpretation in the reception and formulation of this highly influential theory in literary semiotics. Following a revaluation of three major patterns of interpretation of polyphony that have emerged in the global field of literary theory since 1929, as well as Bakhtin’s shift in emphasis in 1963, we find that Bakhtin’s theorizing of polyphony, based on his seemingly inconsistent interpretation of Dostoevsky’s novels, was defined by his own subjectivity as well. An obvious consequence of such subjective predispositions in both the reception of Bakhtin’s theory and his own treatment of Dostoevsky’s polyphonic novels is that they have instigated a type of perpetuating availability bias in approaching the theory of polyphony. This revelation is key to understanding the wholeness of the theory of polyphony from a diachronic perspective. By tracing the cultural and intellectual sources of Dostoevsky’s polyphonic creation, this paper attempts to reframe and restore the Bakhtinian idea of polyphony to its fullness, which we believe can be encapsulated in one phrase: harmony without uniformity.

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Understanding the sources and effects of abandoned, lost, and discarded fishing gear on marine turtles in northern Australia

Conservation Biology ◽

10.1111/cobi.12355 ◽

2014 ◽

Vol 29 (1) ◽

pp. 198-206 ◽

Cited By ~ 47

Author(s):

Chris Wilcox ◽

Grace Heathcote ◽

Jennifer Goldberg ◽

Riki Gunn ◽

David Peel ◽

...

Keyword(s):

Fishing Gear ◽

Northern Australia ◽

Marine Turtles

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Do Heavy Metal Concentrations Pose a Threat to Marine Turtles from the Mediterranean Sea?

Marine Pollution Bulletin ◽

10.1016/s0025-326x(98)00184-2 ◽

1999 ◽

Vol 38 (6) ◽

pp. 497-502 ◽

Cited By ~ 87

Author(s):

Brendan J. Godley ◽

David R. Thompson ◽

Robert W. Furness

Keyword(s):

Heavy Metal ◽

Mediterranean Sea ◽

Metal Concentrations ◽

Heavy Metal Concentrations ◽

Marine Turtles ◽

The Mediterranean

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A Revision of the Subfamily Microscaphidiinae (Platyhelminthes, Digenea, Microscaphidiidae) Parasitic in Marine Turtles (Reptilia, Chelonia)

Australian Journal of Zoology ◽

10.1071/zo9860241 ◽

1986 ◽

Vol 34 (2) ◽

pp. 241 ◽

Cited By ~ 5

Author(s):

D Blair

Keyword(s):

Green Turtle ◽

Chelonia Mydas ◽

Nomen Nudum ◽

Taxonomic Significance ◽

Marine Turtles ◽

As Species ◽

First Time ◽

Species Inquirendae

A revision of the subfamily Microscaphidiinae Looss, 1900 is presented and characters of taxonomic significance discussed. The genus Microscaphidium Looss, 1900, contains M. reticulare (van Beneden, 1859) Looss, 1901 (synonyms M. japonicum Oguro, 1941; M. caballeroi Groschaft, 1977); M. aberrans Looss, 1902 (synonym M. reticulare in part); and M, warui, sp. nov. Confusion in the literature over the identities of M. reticulare and M. aberrans is discussed. A neotype is selected for the former species and a lectotype for the latter. Polyangium linguatula (Looss, 1899) Looss, 1902 (synonyms P. miyajimai Kobayashi, 1921; P. colymbi Poche, 1925; P. longiseminale Chattopadhyaya, 1972) is the sole species in Polyangium Looss, 1902. The genus Angiodictyum Looss, 1902 contains A. parallelum (Looss, 1901) Looss, 1902; A. posterovitellatum Chattopadhyaya, 1972; A. longum, sp, nov.; A. glossoides, sp. nov. Polygorgyra, gen. nov., is proposed for P. cholados, sp. nov. Microscaphidium chelonei Chattopadhyaya, 1972 nec Mehrotra, 1973 and Angiodictyum anteroporum Chattopadhyaya, 1972 are regarded as species inquirendae. Microscaphidium chelonei Mehrotra, 1973 nec Chattopadhyaya, 1972 is a nomen nudum. The following species are recorded for the first time from the green turtle, Chelonia mydas (L.) in Australian waters: Microscaphidium reticulare; M. aberrans; M. warui; Angiodictyum posterovitellatum; A. longum; Polygorgyra cholados.

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Chelonicola and Poulinea, two new gomphonemoid diatom genera (Bacillariophyta) living on marine turtles from Costa Rica

Phytotaxa ◽

10.11646/phytotaxa.233.3.2 ◽

2015 ◽

Vol 233 (3) ◽

pp. 236 ◽

Cited By ~ 21

Author(s):

Roksana Majewska ◽

J. P. Kociolek ◽

Evan W. Thomas ◽

Mario De Stefano ◽

Mario Santoro ◽

...

Keyword(s):

Costa Rica ◽

Marine Mammals ◽

Sea Turtles ◽

Sea Turtle ◽

New Genera ◽

Olive Ridley ◽

Lepidochelys Olivacea ◽

Marine Turtles ◽

The Family ◽

Long Time

Marine mammals such as whales and dolphins have been known for a long time to host a very specific epizoic community on their skin. Less known however is the presence of a similar community on the carapaces of sea turtles. The present study is the first describing new taxa inhabiting sea turtle carapaces. Samples, collected from nesting olive ridley sea turtles (Lepidochelys olivacea) on Ostional Beach (Costa Rica), were studied using light and scanning electron microscopy. Two unknown small-celled gomphonemoid taxa were analysed in more detail and are described as two new genera, closely related to other gomphonemoid genera with septate girdle bands, such as Tripterion, Cuneolus and Gomphoseptatum. Chelonicola Majewska, De Stefano & Van de Vijver gen. nov. has a flat valve face, uniseriate striae composed of more than three areolae, simple external raphe endings, internally a siliceous flap over the proximal raphe endings and lives on mucilaginous stalks. Poulinea Majewska, De Stefano & Van de Vijver gen. nov. has at least one concave valve, uniseriate striae composed of only two elongated areolae, external distal raphe endings covered by thickened siliceous flaps and lives attached to the substrate by a mucilaginous pad. Chelonicola costaricensis Majewska, De Stefano & Van de Vijver sp. nov. and Poulinea lepidochelicola Majewska, De Stefano & Van de Vijver sp. nov. can be separated based on stria structure, girdle structure composed of more than 10 copulae, raphe structure and general valve outline. A cladistics analysis of putative members of the Rhoicospheniaceae indicates that the family is polyphyletic. Chelonicola and Poulinea are sister taxa, and form a monophyletic group with Cuneolus and Tripterion, but are not closely related to Rhoicosphenia, or other genera previously assigned to this family. Features used to help diagnose the family such as symmetry and presence of septa and pseudosepta are homoplastic across the raphid diatom tree of life.

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Marine Wildlife Bycatch Under the CMS: Progress and Prospects

The International Journal of Marine and Coastal Law ◽

10.1163/157180803100380438 ◽

2003 ◽

Vol 18 (2) ◽

pp. 215-240

Keyword(s):

Marine Species ◽

Wild Animals ◽

Migratory Species ◽

Considerable Potential ◽

Marine Turtles ◽

Incidental Capture ◽

Wide Range ◽

Marine Wildlife

AbstractThis article explains the provisions of the Convention for the Conservation of Migratory Species of Wild Animals (CMS) and its subsidiary marine wildlife instruments as they relate to bycatch management. The CMS was primarily developed with the purpose of protecting and conserving migratory species and their habitats. The Convention was initially regarded as little more than a paper accord. Since its inception the CMS has undergone gradual significant changes not only in its scope but also in its geographical coverage. There are ten subsidiary instruments currently in force under the CMS which include regional accords on a wide range of marine species such as cetaceans, marine turtles and pinnipeds. These agreements have considerable potential for regulating the incidental capture of marine wildlife in fisheries. Issues of interest in regard to these agreements include the use of non-binding instruments, and mechanisms for coordination between accords. This article examines the CMS and its subsidiary instruments; it identifies challenges facing the Convention, and provides options for the development of more comprehensive approaches to the management of bycatch.

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Status of Marine Turtles in British Columbia Waters: A Reassessment

The Canadian Field-Naturalist ◽

10.22621/cfn.v118i1.885 ◽

2004 ◽

Vol 118 (1) ◽

pp. 72 ◽

Cited By ~ 3

Author(s):

Donald F. McAlpine ◽

Stan A. Orchard ◽

Kelly A. Sendall ◽

Rod Palm

Keyword(s):

British Columbia ◽

Marine Environment ◽

Chelonia Mydas ◽

Marine Turtle ◽

Dermochelys Coriacea ◽

Concerted Effort ◽

Leatherback Turtles ◽

Marine Turtles ◽

Green Turtles

Marine turtles in British Columbia have previously been considered off course stragglers. Here we document 20 new reports for Green Turtles, Chelonia mydas, and Leatherback Turtles, Dermochelys coriacea, for the province. Until recently there had been no concerted effort to acquire data on marine turtle abundance or frequency off British Columbia. Observations presented here allow a reassessment of marine turtle status in British Columbia waters. We suggest Green Turtles and Leatherbacks should be considered rare vagrants and uncommon seasonal residents, respectively, off British Columbia and that they are a natural part of the British Columbia marine environment.

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