scholarly journals How long do dolphins live? Survival rates and life expectancies for bottlenose dolphins in zoological facilities vs . wild populations

2019 ◽  
Vol 35 (4) ◽  
pp. 1418-1437 ◽  
Author(s):  
Kelly Jaakkola ◽  
Kevin Willis
Keyword(s):  
Bottlenose Dolphins ◽  
Survival Rates ◽  
Wild Populations

scholarly journals Parrot Free-Flight as a Conservation Tool

Diversity ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 254
Author(s):  
Constance Woodman ◽  
Chris Biro ◽  
Donald J. Brightsmith
Keyword(s):  
Antipredator Behavior ◽  
Survival Rates ◽  
Flight Time ◽  
Flight Training ◽  
Wild Food ◽  
Wild Populations ◽  
Free Flight ◽  
Training Technique ◽  
Outdoor Environments ◽  
Raptor Conservation

The release of captive-raised parrots to create or supplement wild populations has been critiqued due to variable survival rates and unreliable flocking behavior. Private bird owners free-fly their parrots in outdoor environments and utilize techniques that could address the needs of conservation breed and release projects. We present methods and results of a free-flight training technique used for 3 parrot flocks: A large-bodied (8 macaws of 3 species and 2 hybrids), small-bodied (25 individuals of 4 species), and a Sun Parakeet flock (4 individuals of 1 species). Obtained as chicks, the birds were hand-reared in an enriched environment. As juveniles, the birds were systematically exposed to increasingly complex wildland environments, mirroring the learning process of wild birds developing skills. The criteria we evaluated for each flock were predation rates, antipredator behavior, landscape navigation, and foraging. No parrots were lost to predation or disorientation during over 500 months of free-flight time, and all birds demonstrated effective flocking, desirable landscape navigation, and wild food usage. The authors conclude that this free-flight method may be directly applicable for conservation releases, similar to the use of falconry methods for raptor conservation.

scholarly journals Survival Rates and Capture Heterogeneity of Bottlenose Dolphins (Tursiops truncatus) in the Shannon Estuary, Ireland

2021 ◽  
Vol 8 ◽  
Author(s):  
Kim E. Ludwig ◽  
Mags Daly ◽  
Stephanie Levesque ◽  
Simon D. Berrow
Keyword(s):  
Range Expansion ◽  
Bottlenose Dolphin ◽  
Site Fidelity ◽  
Bottlenose Dolphins ◽  
Survival Rates ◽  
Adult Survival ◽  
Demographic Parameter ◽  
Resident Population ◽  
The Mean ◽  
Survey Effort

Adult survival is arguably the most important demographic parameter for long-lived species as it has a large impact on population growth, and it can be estimated for cetacean populations using natural markings and mark-recapture (MR) modelling. Here we describe a 26-year study of a genetically discrete, resident population of bottlenose dolphins in the Shannon Estuary, Ireland, conducted by an NGO using multiple platforms. We estimated survival rates (SRs) using Cormack-Jolly-Seber models and explored the effects of variable survey effort, multiple researchers, and changes in camera equipment as well as capture heterogeneity induced by changes in marks and site fidelity variation, all common issues affecting longitudinal dolphin studies. The mean adult SR was 0.94 (±0.001 SD) and thus comparable to the estimates reported for other bottlenose dolphin populations. Capture heterogeneity through variation in mark severity was confirmed, with higher capture probabilities for well-marked individuals than for poorly marked individuals and a “transience” effect being detected for less well-marked individuals with 43% only recorded once. Likewise, both SR and capture probabilities were comparatively low for individuals with low site fidelity to the Shannon Estuary, and SR of these individuals additionally decreased even further toward the end of the study, reflecting a terminal bias. This bias was attributed to non-random temporal migration, and, together with high encounter rates in Brandon Bay, supported the hypothesis of range expansion. Our results highlight the importance of consistent and geographically homogenous survey effort and support the differentiation of individuals according to their distinctiveness to avoid biased survival estimates.

scholarly journals Reproductive outcome and survival of common bottlenose dolphins sampled in Barataria Bay, Louisiana, USA, following the Deepwater Horizon oil spill

2015 ◽  
Vol 282 (1818) ◽  
pp. 20151944 ◽  
Author(s):  
Suzanne M. Lane ◽  
Cynthia R. Smith ◽  
Jason Mitchell ◽  
Brian C. Balmer ◽  
Kevin P. Barry ◽  
...  
Keyword(s):  
Lung Disease ◽  
Oil Spill ◽  
Bottlenose Dolphins ◽  
Survival Rates ◽  
Reference Population ◽  
Deepwater Horizon ◽  
Due Dates ◽  
Apex Predators ◽  
Barataria Bay

Common bottlenose dolphins ( Tursiops truncatus ) inhabit bays, sounds and estuaries across the Gulf of Mexico. Following the Deepwater Horizon oil spill, studies were initiated to assess potential effects on these ecologically important apex predators. A previous study reported disease conditions, including lung disease and impaired stress response, for 32 dolphins that were temporarily captured and given health assessments in Barataria Bay, Louisiana, USA. Ten of the sampled dolphins were determined to be pregnant, with expected due dates the following spring or summer. Here, we report findings after 47 months of follow-up monitoring of those sampled dolphins. Only 20% (95% CI: 2.50–55.6%) of the pregnant dolphins produced viable calves, as compared with a previously reported pregnancy success rate of 83% in a reference population. Fifty-seven per cent of pregnant females that did not successfully produce a calf had been previously diagnosed with moderate–severe lung disease. In addition, the estimated annual survival rate of the sampled cohort was low (86.8%, 95% CI: 80.0–92.7%) as compared with survival rates of 95.1% and 96.2% from two other previously studied bottlenose dolphin populations. Our findings confirm low reproductive success and high mortality in dolphins from a heavily oiled estuary when compared with other populations. Follow-up studies are needed to better understand the potential recovery of dolphins in Barataria Bay and, by extension, other Gulf coastal regions impacted by the spill.

scholarly journals Integrating high-speed videos in capture-mark-recapture studies of insects

2020 ◽  
Author(s):  
Rassim Khelifa ◽  
Hayat Mahdjoub ◽  
Leithen M'Gonigle ◽  
Claire Kremen
Keyword(s):  
High Speed ◽  
Survival Rates ◽  
Effect Sizes ◽  
Effective Management ◽  
Wild Populations ◽  
Mark Recapture ◽  
Non Invasive ◽  
Wide Range ◽  
Demographic Covariates ◽  
Dragonfly Species

Capture-mark-recapture (CMR) studies have been used extensively in ecology and evolution. While it is feasible to apply CMR in some animals, it is considerably more challenging in small fast-moving species such as insects. In these groups, low recapture rates can bias estimates of demographic parameters, thereby, handicapping effective management of wild populations. Here we use high-speed videos (HSV) of the adults of two large dragonfly species that rarely land and, thus, are particularly challenging for CMR studies. We specifically test whether HSV, compared to conventional eye observations, increases the “resighting” rates and improves the certainty of the estimates of survival rate, and the effects of demographic covariates on survival rates. We show that the use of HSV increases the number of resights substantially. HSV improved our estimates of resighting and survival probability which were either under- or overestimated with the conventional observations. HSV increased the accuracy of the estimates of effect sizes of important covariates (age and body size). Integrating HSV in CMR of highly mobile animals is valuable because it is easy, non-invasive, and has the potential to improve demographic estimates. Hence, it opens the door for a wide range of research possibilities on species that are traditionally difficult to monitor, including within insects, birds, and mammals.

The Analysis of Mortality and Survival Rates in Wild Populations of Mosquitoes

1981 ◽  
Vol 18 (2) ◽  
pp. 373 ◽  
Author(s):  
A. N. Clements ◽  
G. D. Paterson
Keyword(s):  
Survival Rates ◽  
Wild Populations

Ultrastructural Changes in Three Different Mammalian Cells Following Ultraviolet Laser Irradiation

1972 ◽  
Vol 30 ◽  
pp. 350-351
Author(s):  
K. Shankar Narayan ◽  
Kailash C. Gupta ◽  
Tohru Okigaki
Keyword(s):  
Ultraviolet Light ◽  
Mammalian Cells ◽  
Biological Effects ◽  
Survival Rates ◽  
Chinese Hamster ◽  
Cell Types ◽  
Differential Sensitivity ◽  
Ultrastructural Changes ◽  
Ultraviolet Laser

The biological effects of short-wave ultraviolet light has generally been described in terms of changes in cell growth or survival rates and production of chromosomal aberrations. Ultrastructural changes following exposure of cells to ultraviolet light, particularly at 265 nm, have not been reported.We have developed a means of irradiating populations of cells grown in vitro to a monochromatic ultraviolet laser beam at a wavelength of 265 nm based on the method of Johnson. The cell types studies were: i) WI-38, a human diploid fibroblast; ii) CMP, a human adenocarcinoma cell line; and iii) Don C-II, a Chinese hamster fibroblast cell strain. The cells were exposed either in situ or in suspension to the ultraviolet laser (UVL) beam. Irradiated cell populations were studied either "immediately" or following growth for 1-8 days after irradiation.Differential sensitivity, as measured by survival rates were observed in the three cell types studied. Pattern of ultrastructural changes were also different in the three cell types.

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