Injuries, healing and management of common dolphins (Delphinus delphis) in human-impacted waters in the south Iberian Peninsula

Author(s):  
Liliana Olaya-Ponzone ◽  
Rocío Espada ◽  
Estefanía Martín Moreno ◽  
Isabel Cárdenas Marcial ◽  
José C. García-Gómez

AbstractThis study focuses on the dolphins populating the water between Gibraltar and Algeciras in the south Iberian Peninsula, an area subjected to pressure due to high human activity. The area is considered an important feeding and breeding ground for common dolphins (Delphinus delphis). Due to the degree of residence of some specimens, and the large gap in knowledge about the evolution of wounds in D. delphis specimens with lacerations, this work sought to perform the following analyses: identify lacerated individuals; characterize sequences of ‘before – during – after’ with respect to the occurrence of lacerations; and associate the type of injury with its severity. This work will inform future studies by expanding a database on injured individuals and contribute to periodical monitoring of specimens that frequent these geographic areas. Between 2013 and 2017, we were able to track the healing process of five injured individuals of common dolphins from a whale-watching platform thanks to photo identification. The animals exhibited fresh external wounds from different sources. In the majority of individuals, the wound-healing processes lasted 3–21 weeks. The frequency with which sightings are made and knowledge about the local population will help track injured animals, follow their wound evolution, and document their survival rates. The documented injuries inflicted by human interactions described in this paper may include fishing interactions and propeller strikes, probably as a consequence of the high intensity of recreational fishing and whale-watching activities in the area.

2015 ◽  
Vol 72 (8) ◽  
pp. 2438-2449 ◽  
Author(s):  
Ana Marçalo ◽  
Isidora Katara ◽  
Diana Feijó ◽  
Helder Araújo ◽  
Isabel Oliveira ◽  
...  

Abstract Interactions between cetaceans and the purse-seine fishery operating along the whole Portuguese continental coast were studied based on on-board observations from 2010 to 2011. Cetacean presence and mortality were estimated and characteristics under which interactions were most likely to occur were identified. Observations were made on 163 fishing trips (0.7% of the average annual number of fishing trips) and 302 fishing operations/hauls. Cetaceans were present during 16.9% of fishing events; common dolphins (Delphinus delphis) accounted for 96% of occurrences, mostly overnight in summer and early autumn. Regression models showed that cetacean presence during a fishing set was significantly (p < 0.05) associated with sardine catches, effort, and latitude/longitude. Encirclement and mortality occurred in 2.3 and 1.0% of fishing events, respectively. Encircled species were the common dolphin, bottlenose dolphin (Tursiops truncatus), and harbour porpoise (Phocoena phocoena), but only common dolphin showed mortality (three individuals); raised to fleet level, estimated total mortality rates of common dolphins were 69 (95% CI 37–110) in the north and 91 (95% CI 55–165) in the south for 2010 and 78 (95% CI 47–140) in the south only for 2011. The estimated annual mortality rate due to purse seining is 113 (95% CI 3–264) common dolphins, which is ∼0.63% of the current most optimistic estimate of population size for the Portuguese fishing area (SCANS II). The wide confidence limits, as well as variation between years, reflect low observer coverage, emphasizing the need for increased monitoring to cover gaps in the spatial and seasonal distribution of observer effort and provide reliable estimates of bycatch.


2016 ◽  
Vol 3 (9) ◽  
pp. 160478 ◽  
Author(s):  
Suzanne Mason ◽  
Chandra Salgado Kent ◽  
David Donnelly ◽  
Jeffrey Weir ◽  
Kerstin Bilgmann

Short-beaked common dolphins ( Delphinus delphis ) are typically considered highly mobile, offshore delphinids. This study assessed the residency of a small community of short-beaked common dolphins in the shallow, urbanized Port Phillip Bay, south-eastern Australia. The ability to identify common dolphins by their dorsal fin markings and coloration using photo-identification was also investigated. Systematic and non-systematic boat surveys were undertaken between 2007 and 2014. Results showed that 13 adult common dolphins and their offspring inhabit Port Phillip Bay, of which 10 adults exhibit residency to the bay. The majority of these adults are reproductively active females, suggesting that female philopatry may occur in the community. Systematic surveys conducted between 2012 and 2014 revealed that the dolphins were found in a median water depth of 16 m and median distance of 2.2 km from the coast. The shallow, urbanized habitat of this resident common dolphin community is atypical for this species. As a result, these common dolphins face threats usually associated with inshore bottlenose dolphin communities. We suggest that the Port Phillip Bay common dolphin community is considered and managed separate to those outside the embayment and offshore to ensure the community's long-term viability and residency in the bay.


2017 ◽  
Vol 43 (3) ◽  
pp. 264-278 ◽  
Author(s):  
Krista E. Hupman ◽  
Matthew D. M. Pawley ◽  
Catherine Lea ◽  
Charli Grimes ◽  
Sabrina Voswinkel ◽  
...  

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
George Deryabin ◽  
Simonas Grybauskas

Abstract Background The purpose of this study was to analyze medium-to-long-term implant success and survival rates, and lower lip sensory disturbance after placement of dental implants with simultaneous inferior alveolar nerve (IAN) repositioning. Methods Fifteen patients (3 men, 12 women) treated in two centers were included in this retrospective study. The ages of the participants ranged from 19 to 68. A total of 48 dental implants were placed in 23 posterior mandibular segments simultaneously with IAN transposition or lateralization. The residual bone above the IAN ranged from 0.5 to 7.0 mm. Crestal bone changes were measured using cone beam computed tomography (CBCT) images. Disturbance of the IAN was evaluated subjectively using a modified questionnaire. Results The healing process was uneventful in fourteen patients. In one patient, spontaneous fracture of the operated mandible occurred on tenth day after the surgery. The implant in the fracture line was removed at the time of open reduction and fixation. One more implant was lost after 5 years of loading. Therefore, the overall dental implant survival rate was 95.8%, whereas all implants in function were judged as successful after a follow-up period of 1 to 10 years. Transient neurosensory disturbances (ND) were observed in all patients who underwent IAN lateralization and IAN transposition. At follow-up times of 3 years, 5 years, and 10 years, weak hypoesthesia remained in two subjects treated with IAN transposition. None of the patients developed neuropathic pain after the procedure. Conclusions Within the limitations of this study, we conclude that reconstruction of severely resorbed mandibles with dental implants in conjunction with IAN repositioning is an effective and reliable technique. Although neurosensory disturbances are the most common complication after surgery, they tend to resolve over time. Advanced surgical skills are required to perform this technique.


1988 ◽  
Vol 58 (1) ◽  
pp. 79-87
Author(s):  
Jos Notenboom

Metahadzia uncispina n. sp. is described, being the second species of the genus on the Iberian Peninsula. The new species, well characterized by the transformation of the apical spine on the endopodite of the male uropod 2, is undoubtedly closely related with M. tavaresi (Mateus & Mateus, 1972) from the south of Portugal. Comments are made about recent emendations of the original concept of the genus Metahadzia Stock, 1977.


2004 ◽  
Vol 13 (14) ◽  
pp. 2641-2660 ◽  
Author(s):  
Esther Giménez ◽  
Manuel Melendo ◽  
Francisco Valle ◽  
Francisco Gómez-Mercado ◽  
Eusebio Cano

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