scholarly journals Habitat use of common dolphin (Delphinus sp.) in the Mochima National Park, Sucre, Venezuela.

2022 ◽  
Vol 22 (1) ◽  
pp. 129-146
Author(s):  
Alimar Molero-Lizarraga ◽  
Guillermo Barreto ◽  
Sergio Cobarrubia-Russo
Keyword(s):  
Habitat Use ◽  
Group Size ◽  
National Park ◽  
Grid Cell ◽  
Size Composition ◽  
Observation Time ◽  
Common Dolphin ◽  
Conservation Policies ◽  
Incidence Studies ◽  
The Common

In Venezuela, common dolphin (Delphinus sp.) is considered the cetacean with the highest incidence. Studies in the region indicate a possible isolated coastal population so called Venezuelan stock   settled mainly in the northeast of the country.  . The objective of this study is to describe the habitat use of common dolphin in the Mochima National Park (MNP), a protected area with a high and growing anthropic pressure. Seventy surveys were carried out, with predefined survey route, from September 2009 to August 2010. Each group sighted was monitored while possible to a maximum of 30min.. During this time we registered location (Latitude-longitude), behaviour, group size and composition every 5min. Additionally, environmental variables were assessed from the sight location in a nautical chart. The study area was divided into a grid (cell: 500 x 500m) and the Coefficient of Area Use (CAU) was calculated for each cell. The proportion of the total observation time where the common dolphin displayed behaviours into the areas being used was estimated. A logistic regression model was applied to identify the variables that better explained usage pattern. In 55h of observation, 111 groups were recorded. The common dolphin used the habitat differentially, showing preferences for shallow areas  near to the coast. Areas of greatest intensity of use were Tigrillo inlet and the northeast of the Caracas Islands. The probability of presence of dolphins decreased with depth and distance to the coast. Common dolphin invested more time in feeding and socializing activities. Behaviours were significantly dependent of season, group size, composition, depth and distance to the coast. Finally, these data on habitat use and behaviour allow the identification of priority habitats. Throughout the year, the MNP provided areas for refuge, feeding and resting. , It is therefore imperative to promote management and conservation policies that prevent the negative impacts of the increasing   tourism and fishing activities we observed in this Park.

scholarly journals Contributions to Management Strategies in the NE Atlantic Regarding the Life History and Population Structure of a Key Deep-Sea Fish (Mora moro)

Biology ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 522
Author(s):  
Régis Santos ◽  
Wendell Medeiros-Leal ◽  
Osman Crespo ◽  
Ana Novoa-Pabon ◽  
Mário Pinho
Keyword(s):  
Population Structure ◽  
Life History ◽  
Deep Sea ◽  
Management Strategies ◽  
Size Composition ◽  
Large Size ◽  
The Common ◽  
Fishing Impacts ◽  
Sea Fish

With the commercial fishery expansion to deeper waters, some vulnerable deep-sea species have been increasingly captured. To reduce the fishing impacts on these species, exploitation and management must be based on detailed and precise information about their biology. The common mora Mora moro has become the main deep-sea species caught by longliners in the Northeast Atlantic at depths between 600 and 1200 m. In the Azores, landings have more than doubled from the early 2000s to recent years. Despite its growing importance, its life history and population structure are poorly understood, and the current stock status has not been assessed. To better determine its distribution, biology, and long-term changes in abundance and size composition, this study analyzed a fishery-dependent and survey time series from the Azores. M. moro was found on mud and rock bottoms at depths below 300 m. A larger–deeper trend was observed, and females were larger and more abundant than males. The reproductive season took place from August to February. Abundance indices and mean sizes in the catch were marked by changes in fishing fleet operational behavior. M. moro is considered vulnerable to overfishing because it exhibits a long life span, a large size, slow growth, and a low natural mortality.

scholarly journals Endoscopic Study of the Oral and Pharyngeal Cavities in the Common Dolphin, Striped Dolphin, Risso’s Dolphin, Harbour Porpoise and Pilot Whale: Reinforced with Other Diagnostic and Anatomic Techniques

Animals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1507
Author(s):  
Álvaro García de los Ríos y Loshuertos ◽  
Marta Soler Laguía ◽  
Alberto Arencibia Espinosa ◽  
Francisco Martínez Gomariz ◽  
Cayetano Sánchez Collado ◽  
...  
Keyword(s):  
Oral Cavity ◽  
Common Dolphin ◽  
Resonance Imaging ◽  
Pilot Whale ◽  
Anatomical Structures ◽  
Vascular Plexus ◽  
Endoscopic Study ◽  
Main Technique ◽  
The Common ◽  
Magnetic Resonance Imaging Mri

In this work, the fetal and newborn anatomical structures of the dolphin oropharyngeal cavities were studied. The main technique used was endoscopy, as these cavities are narrow tubular spaces and the oral cavity is difficult to photograph without moving the specimen. The endoscope was used to study the mucosal features of the oral and pharyngeal cavities. Two pharyngeal diverticula of the auditory tubes were discovered on either side of the choanae and larynx. These spaces begin close to the musculotubaric channel of the middle ear, are linked to the pterygopalatine recesses (pterygoid sinus) and they extend to the maxillopalatine fossa. Magnetic Resonance Imaging (MRI), osteological analysis, sectional anatomy, dissections, and histology were also used to better understand the function of the pharyngeal diverticula of the auditory tubes. These data were then compared with the horse’s pharyngeal diverticula of the auditory tubes. The histology revealed that a vascular plexus inside these diverticula could help to expel the air from this space to the nasopharynx. In the oral cavity, teeth remain inside the alveolus and covered by gums. The marginal papillae of the tongue differ in extension depending on the fetal specimen studied. The histology reveals that the incisive papilla is vestigial and contain abundant innervation. No ducts were observed inside lateral sublingual folds in the oral cavity proper and caruncles were not seen in the prefrenular space.

Population abundance of the common hippopotamus Hippopotamus amphibius in the Haut Niger National Park, Republic of Guinea / Abondance de la population d'hippopotame commun Hippopotamus amphibius dans le Parc National du Haut Niger, République de Guinée

Mammalia ◽  
2006 ◽  
Vol 70 (1-2) ◽  
Author(s):  
David Brugière ◽  
Bakary Magassouba ◽  
Amidou Sylla ◽  
Halimou Diallo ◽  
Mamadou Sow
Keyword(s):  
National Park ◽  
Buffer Zone ◽  
Wet Season ◽  
Republic Of Guinea ◽  
Hippopotamus Amphibius ◽  
The Status ◽  
Grazing Area ◽  
The Common ◽  
The Republic

AbstractThe Republic of Guinea is thought to contain the largest population of common hippopotamus in West Africa. However, no systematic field survey has been carried out recently and the information available is limited to informal observations. To clarify the status of the common hippopotamus in Guinea, we carried out a biannual population survey along the section of the Niger River (the largest river in Guinea) within the Haut Niger National Park. We counted 93 hippopotamuses in 28 groups in the dry season and 77 hippopotamuses in 23 groups in the wet season. Mean group size and number of neonates did not change between the seasons. Hippopotomuses were more numerous along the river sections bordering uncultivated floodplains. This underlines the significance of this habitat (which is used as a grazing area) for conservation of this species. Haut Niger National Park is the most important protected area in Guinea for conservation of the common hippopotamus. Hippopotamus-human and -cattle conflicts in terms of floodplain use in the park's buffer zone should be closely monitored. Floodplain conversion to rice fields represents one of the most important threats to the long-term conservation of hippopotamus populations in Guinea.

scholarly journals Tourism affects the behavioural budget of the common dolphin Delphinus sp. in the Hauraki Gulf, New Zealand

2008 ◽  
Vol 355 ◽  
pp. 287-295 ◽  
Author(s):  
KA Stockin ◽  
D Lusseau ◽  
V Binedell ◽  
N Wiseman ◽  
MB Orams
Keyword(s):  
New Zealand ◽  
Common Dolphin ◽  
The Common

scholarly journals The major vegetation communities of the Augrabies Falls National Park, Northern Cape. 1. The southern section

Koedoe ◽  
1996 ◽  
Vol 39 (2) ◽  
Author(s):  
H. Bezuidenhout
Keyword(s):  
Plant Communities ◽  
Wildlife Management ◽  
National Park ◽  
Management Programme ◽  
Vegetation Map ◽  
Conservation Policies ◽  
Community Classification ◽  
Northern Cape ◽  
Plant Community Classification ◽  
Southern Section

Classification, description and mapping of the vegetation of the Augrabies Falls National Park, Northern Cape, were initiated. The classification is intended to serve as a basis for the establishment of an efficient wildlife management programme as well as conservation policies for the Augrabies Falls National Park. Using the BBPC suite, according to Braun-Blanquet procedures to classify the vegetation of the southern section of the Augrabies Falls National Park, six major plant communities are recognised. A hierarchical plant community classification, description, ecological interpretation and a vegetation map are presented.

scholarly journals Coyote (Canis latrans) Habitat use and Mortality in Grand Teton National Park and Suburban-Agricultural Areas of Jackson Hole, Wyoming

2000 ◽  
Vol 24 ◽  
pp. 51-59
Author(s):  
Matt McGee ◽  
Stan Anderson ◽  
Doug Wachob
Keyword(s):  
Habitat Use ◽  
National Park ◽  
Agricultural Land ◽  
Canis Latrans ◽  
Short Interval ◽  
Agricultural Area ◽  
Grand Teton National Park ◽  
Use Patterns ◽  
Jackson Hole ◽  
Agricultural Areas

A study of coyote (Canis latrans) habitat use and mortality in Grand Teton National Park and the suburban-agricultural land surrounding Jackson, WY was conducted between September 1999 and August 2000. This research focused on the influence of human development, habitat type, topography, and simulated wolf presence on coyote habitat use and on coyote mortality patterns in undeveloped and suburban-agricultural land. The overall goal of this project was to provide baseline information on the coyote population in Jackson Hole that can be used in the future to determine what, if any, impact wolves and human developments may have on coyotes. There were a total of fifteen radio-collared coyotes in the suburban-agricultural area and fourteen radio collared coyotes in Grand Teton National Park and adjacent areas in the National Elk Refuge and Bridger-Teton National Forest. Marked coyotes were tracked weekly using short interval telemetry relocations and triangulation to determine habitat use patterns. During the winter, track transects were skied weekly and coyote trails were backtracked and mapped using hand held GPS units to determine fine scale habitat use patterns. Coyote mortality was determined via telemetry and direct observation. Preliminary data analyses suggest that coyotes use mainly sagebrush-grasslands or forest-shrub-grass edge areas and avoid forest interior areas. Coyotes frequently use trails and roads in the undeveloped area when moving long distances. Preliminary analysis also indicates that roads and trails are used in a greater proportion than their abundance on the landscape. Coyotes were frequently observed using riparian corridors to move between open meadows in the suburban-agricultural area. There is some evidence that suggests coyotes selectively travel fences and irrigation ditches for long distances in agricultural areas. The movement data also suggests that coyotes avoid developed areas during the day and travel in these developed areas at night. The data on coyote locations suggests some avoidance of wolf urine scent grids in the undeveloped area, but not in the developed area. Coyote mortality was primarily human caused, and coyotes that were male, transient, and lived in the suburban-agricultural area were the most commonly killed animals.

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