Studies in this category investigate various aspects of bottlenose dolphin reproduction. Included in this category are studies that have contributed to the knowledge and understanding of hormones, breeding, pregnancies, fetal development, lactation and nutrition, and rearing of young. This is an important area of study as all of these factors have a role to play in species sustainability, and survival, both under human care and in the wild. Click on a study title below to read more!
Assessment of Fetal Development and Later Term Gestational Calf Viability
Project Investigators: L.Rae Stone, D.V.M.
Affiliate Organizations: Dolphin Quest
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 1993
Project Description: Monthly diagnostic ultrasound examinations were performed through five pregnancies at the Dolphin Quest facility on the Big Island of Hawaii. Dolphins were trained for voluntary positioning for the procedures. Fetal growth was charted for both skull and thorax diameter. Cardiac development and function were recorded and fetal viability indices were defined and assessed. The information developed in this study makes possible a simple means of determining the gestational age of a Tursiops fetus, with application to population assessment studies in the field. It also provides a means of determining fetal viability in the critical third trimester of development.
Changes in Body Mass and Total Body Water in Three Species of Odonocetes
Project Investigators: Shannon Atkinson, Ph.D. and Molly Lucas
Affiliate Organizations: University of Hawaii at Honolulu and Dolphin Quest
Species: Tursiops truncatus, Delphinapterus leucas, and Lagenorhynchus obliquiden
Dolphin Quest Supported: 1994
Project Description: The goal is that one day this comparable model will be able to be used as an assessment tool to determine the metabolic changes in dolphins during pregnancy and learn more about the energetic reproductive strategies of bottlenose dolphins. A better understanding of the pattern of energy partitioning will aid in the management of pregnant animals in controlled settings and will aid in the management of conservation of wild population.
Dolphin Milk as an Indicator of Reproductive Status
Project Investigators: Kristi West, Carpenter, J. Oftedal, O.
Affiliate Organizations: University of Hawaii, Manoa; L’Universite de la Polynesie Francaise, Papeete; National Zoological Park, Smithsonian Institution, Washington, DC
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 1997
Project Description: Investigated milk sampling as an alternative to blood collection for measurement of hormone levels. Milk sampling could be used to monitor ovarian activity in trained bottlenose dolphins. Milk analysis could be used to diagnose pregnancy and predict the time of ovulation, which would be useful in breeding management.
Marine Mammal/Conservation Benefit:
- Less invasive method of determining hormone levels in dolphins under human care
- Increased understanding of hormone variation and reproductive cycle
- Enhanced breeding management
- Application of knowledge gained from animals under human care to wild populations
Dolphin Milk to Study Reproduction
Project Investigators: Kristi West, Ph.D. and Shannon Atkinson, Ph.D.
Affiliate Organizations: University of Hawaii at Manoa and Dolphin Quest
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 1997-2002
Project Description: This project determined that a correlation exists between milk and blood plasma when measuring progesterone, a reproductive hormone, in bottlenose dolphins. This research provides validation of a non-invasive, alternative method to blood collection for measurement of hormone levels in bottlenose dolphins. Potential applications of milk analysis include diagnosing pregnancy and predicting the time of ovulation useful in breeding management. This method may contribute to increased understanding of dolphin reproduction by providing a means to ascertain the reproductive status of dolphins. This information may lead to greater reproductive success and a higher level of animal care for dolphins.
Maternal Investment Strategies in Wild Bottlenose Dolphins
Project Investigators: Caryn Weiss Owen, M.S. and Randall Wells, Ph.D.
Affiliate Organizations: University of California, Santa Cruz, Conservation Biology Department of the Chicago Zoological Society, Illinois, and Dolphin Quest
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2000 – 2002
Project Description: This research examined the potential differences in parental investment strategies among different age classes of females to determine if varying behavioral patterns contribute to differential calf survivorship. Knowledge of maternal behavioral factors affecting calf survival is of importance to management of both wild and captive populations of bottlenose dolphins and may contribute to the understanding of successful community recruitment, which is the basis for many ecological management plans.
Dolphin Hormones: Establishing Baseline Values According to Reproductive Condition
Project Investigators: Kristi West, Erin Hanahoe
Affiliate Organizations: University of Hawaii, Manoa; L’Universite de la Polynesie Francaise. Papeete
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2001
Project Description: Blood, serum and milk samples voluntarily collected from bottlenose dolphins. Samples used to determine factors affecting hormone levels according to the reproductive condition.
Marine Mammal Benefit/Conservation Benefit:
- Increased understanding of hormone variation according to reproductive condition
- Enhanced breeding management
- Application of knowledge gained from animals under human care to wild populations
Keeping the Fetus Cool: Reproductive Thermoregulation During Pregnancy in Bottlenose Dolphins
Project Investigators: D. Ann Pabst, William A. McLellan, Erin Meagher, and Sentiel Rommel
Affiliate Organizations: University of North Carolina at Wilmington and Dolphin Quest
Species: Bottlenose dolphins (Tursiops truncatus)
Dolphin Quest Supported: 2003
Project Description: Bottlenose dolphins possess a specialized vascular structure called a counter-current heat exchanger (CCHE), that functions to cool their reproductive tissues. Heat is transferred from the warm arterial blood to the relatively cool venous blood at a reproductive CCHE site in the reproductive tissue. This allows cooled arterial blood to supply the intra-abdominal testes and the pregnant uterus. Project will test whether CCHE functions also deliver relatively cooled blood to the fetus, the following methods will be employed: 1) determine the position of the CCHE, 2) take body temperature at two positions (one at the CCHE and the other at an area unaffected by the CCHE), 3) maintain a log of deep body temperature over time, and 4) collect other husbandry and health data. This project will directly test the hypothesis that female dolphins use the reproductive CCHE to cool the developing fetus. This study may also provide important insights into the thermal needs of pregnant dolphins.
Swimming Kinetics in Calves
Project Investigators: Shawn Noren Kramer, Williams, T. M
Affiliate Organizations: University of California, Santa Cruz
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2003
Project Description: This study aims to determine:
- If the cost of swimming for the dolphin calf is lower when swimming in echelon position (calf swims alongside mother’s dorsal fin to gain a hydrodynamic boost) than when swimming alone
- If the cost of swimming for the mother is similar when swimming alone and when accompanied by her calf
- The age of the calf when the cost of swimming alone is equivalent to the cost of swimming in echelon position
- The upper swim speed at which the mom-calf positioning is disrupted
Marine Mammal / Conservation Benefit:
- Adds to the existing base of scientific knowledge
- Important for decisions regarding the policies for the dolphin chases associated with the activities of the tuna purse-seine fishery
- Potential application to limit animal mortality associated with purse-seine fisheries
Does Free-Riding Behavior Enhance Swimming Efficiency and Reduce Locomotor Costs of Dolphin Calves?
Project Investigators: Dr. Shawn R. Noren
Affiliate Organizations: Southwest Fisheries Science Center, NOAA, and Dolphin Quest Hawaii
Species: Atlantic bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2003 – 2007
Project Description: This study examines the influence of swim speed on mom-calf swimming kinematics. Death of calves during tuna purse-seine fishery chases may explain why depleted dolphin populations in the Eastern tropical Pacific are not recovering. The results of this study add to the current base of scientific knowledge and are important for decisions regarding the policies for the dolphin chases associated with the activities of the tuna purse-seine fishery in the ETP.
Conservation Benefit: This study helps to determine the ability of dolphin calves to keep up with their moms during the chase that is part of the Eastern Tropical Pacific tuna fishery. Findings suggest that when the fisherman are enclosing the tuna within the giant purse-seine net enclosure, dolphin calves are separated from moms, thereby being left alone and subject to predation subsequent to the separation. This has long been the suspected reason that dolphin populations in this region have not recovered from previous losses associated with this fishery. With the findings of this project, scientists have a direct cause and effect relationship between the chase, and the related loss of dolphin calves.
Investigation of Contaminant Concentration in Dolphin Milk
Project Investigators: John Kucklick, Ph.D., Rebecca Pugh; Teri Rowles, D.V.M./Ph.D.
Affiliate Organizations: NIST Hollings Marine Laboratory; NOAA National Marine Fisheries Service
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2004 – 2005
Project Description: This project aims at investigating contaminant concentrations in dolphin milk over time and a possible relationship with blood values. Milk and blood samples from mother and calf pairs at Dolphin Quest Bermuda will be examined in conjunction with field data from the Sarasota Dolphin Research Program to help build a risk assessment model for the exposure of first born dolphins to organic pollutants. This project aims at providing crucial information to better understand the effects of contaminants on nursing dolphins.
Milk Mineral Values in Free-Ranging and Captive Bottlenose Dolphins
Project Investigators: Shah, R.S., Kristi West, Oftedal, O.T., Randy S.Wells, Jay Sweeney
Affiliate Organizations: University of Hawaii, Indianapolis Zoo Dolphin Reproduction Symposium
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2005
Project Description: Analysis of mineral values in milk samples from free-ranging and captive bottlenose dolphins
Marine Mammal/Conservation Benefit:
- Increased understanding of the composition of dolphin milk
- Application in the care of stranded/orphaned or hand –reared calves
Swimming Kinematics in Dolphin Calves
Project Investigators: Shawn Noren-Kramer
Affiliate Organizations: Institute of Marine Science, University of California, Santa Cruz
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2005
Project Description: Demonstrated that although echelon swimming (calf swims alongside mother’s dorsal fin to gain a hydrodynamic boost) enables calves to travel at group speed with decreased tail beat frequency and stroke amplitude, the erratic movements and speeds experienced during a fishery related chase could disrupt this position. Ultimately independently swimming 0‐1 month‐old calves are incapable of adult swim speeds and thus are unlikely able to maintain chase speeds.
Marine Mammal/Conservation Benefit:
- Adds to the existing base of scientific knowledge
- Informs important for decisions regarding the policies for the dolphin chases associated with the activities of fisheries
- Potential application to limit animal mortality associated with fisheries
Artificial Insemination
Project Investigators: Todd Robeck, Jay Sweeney, Rae Stone, Michelle Campbell
Affiliate Organizations: SeaWorld, Dolphin Quest
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2005 – 2008, 2011
Project Description: Artificial insemination (AI) was planned with dolphins located at Dolphin Quest Hawaii. This project involved monthly monitoring of bottlenose dolphins who were pregnant due to successful artificial insemination. This included fetal growth data, urine samples and hormone tracking.
Marine Mammal/Conservation Benefit:
- Successful Artificial insemination could offer an alternative the need for cooperative breeding loans of animals between facilities
- Increased genetic diversity of human care population
- Development of Artificial Insemination techniques that could be applied with other marine mammal species
Investigations into Dolphin Physiology: Nutritional Requirements for Calves
Project Investigators: Kristi West
Affiliate Organizations: Hawaii Pacific University
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2005 – 2009
Project Description: Focused on validation of the TMAO assay for dolphin serum and milk samples. Developed sample preparation methods to ensure that both of these biological fluids can be reliably assayed for the TMAO biomarker. Completed validations have confirmed that milk intake does not produce a signal that can be confused with solid food intake and we are now at the stage of conducting feed trials in 2006.
Marine Mammal Benefit/Conservation Benefit:
- Increased understanding of the nutritional requirements of calves
- Application in the care of stranded/orphaned or hand-reared calves
Fetal Dolphin Echocardiography Study
Project Investigators: Mark Sklansky
Affiliate Organizations: University of Southern California, Children’s Hospital Los Angeles
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2006
Project Description: The purpose of this study was to evaluate the structure and function of the fetal dolphin heart. Important lessons learned include the ideal size for imaging (beyond six months), the inadequacy of passive restraint, and the importance of behavioral considerations for fetal cardiac imaging.
Marine Mammal/Conservation Benefit: Results from this study will help advance dolphin veterinary medicine by providing normal data and images of fetal dolphin hearts for comparison to cases of fetal distress and abnormal development.
Dolphin Fasting and Feeding Trials
Project Investigators: Kristi West
Affiliate Organizations: Hawaii Pacific University
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2007-2008
Project Description: The goal of this project is to establish the difference between feeding and fasting states in wild bottlenose dolphins. The samples collected at Dolphin Quest Oahu will be used specifically to establish biomarker uptake and excretion in bottlenose dolphins for either TMAO or arsenobetaine (AsB), another biomarker that may prove useful for interpreting past feed history.
Marine Mammal/Conservation Benefit: Collecting of baseline data in a controlled experimental environment will allow for the more meaningful analysis of fasting and feeding data collected in wild and or stranded animals.
Mother‐Calf Echelon Swimming Analyses
Project Investigators: Shawn Noren-Kramer
Affiliate Organizations: Institute of Marine Science, University of California, Santa Cruz
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2007-2012
Project Description: This project involved further analyses on the mother‐calf swimming kinematics study previously funded and supported by Dolphin Quest and to prepare an additional manuscript.
Marine Mammal/Conservation Benefit: This study helps to determine the ability of dolphin calves to keep up with their mother during the chase that is part of the Eastern Tropical Pacific tuna fishery. Findings suggest that when the fisherman are enclosing the tuna within the giant purse-seine net enclosure, dolphin calves are separated from their mother, thereby being left alone and subject to predation subsequent to the separation. This has long been the suspected reason that dolphin populations in this region have not recovered from previous losses associated with this fishery. With the findings of this project, scientists have a direct cause and effect relationship between the chase, and the related loss of dolphin calves.
Ultrasonography as a Tool for the Routine Monitoring of Fetal Development in Tursiops truncatus
Project Investigators: Tom Cardy
Affiliate Organizations: The Royal Veterinary College, London; Dolphin Quest Bermuda
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2008
Project Description: The breeding program at Dolphin Quest Bermuda presents a unique experimental setting on which to base an analysis: females were bred at the same time in a controlled environment, all calves were born successfully and are flourishing and extensive ultrasound data was routinely collected around a variety of physiological parameters.
Marine Mammal/Conservation Benefit: Analysis of the data would provide useful Bermuda–specific benchmark information on which to compare the future development of calves, whilst also providing the foundations for a potential paper or poster on artificial insemination in Tursiops truncatus.
Fatty Acid and Proximate Analysis of Bottlenose Dolphin (Tursiops truncatus) Milk and Prey
Project Investigators: White, W.
Affiliate Organizations: Hawaii Pacific University
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2008 – 2010
Project Description: This project investigated factors that could affect milk composition, specifically diet of the mother, and described the fatty acids found in dolphin milk and prey to determine if milk is viable tissue to predict dietary history of wild dolphin populations.
Marine Mammal/Conservation Benefit: If milk sampling is a viable means for predicting dietary history, this methodology could be applied to field studies with wild dolphins. This would allow for a more complete collection of relative data during these field health assessments.
The Quantity and Quality of Milk Intake in Dolphin Calves: An Expansion of Project Newborn
Project Investigators: Kristi West, Oftedal, O., Carptenter, J.
Affiliate Organizations: Hawaii Pacific University, Kaneohe, HI; National Zoological Park, Washington DC; University of Hawaii at Manoa, Honolulu
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2009
Project Description: This project aims to quantify nutrient transfer from bottlenose dolphin lactating mothers to their calves, while simultaneously examining body fat reserves and calf growth.
Marine Mammal/Conservation Benefit:
- Increased understanding of the nutritional requirements of calves
- Application in the care of stranded/orphaned or hand –reared calves
Relaxin and Progesterone During Pregnancy and Early Post-partum in Association with Live and Stillborn Calves in Bottlenose Dolphins (Tursiops truncatus)
Project Investigators: Bergfelta, D.R., Steinetzb, B. G., Lasanob, S., Kristi West, Michelle Campbell, Adams, G. P.
Affiliate Organizations: US Environmental Protection Agency, Washington DC; New York University School of Medicine, Tuxedo, NY; Hawaii Pacific University, Kaneohe, HI
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2009-2010
Project Description: Analyzed the levels of hormones progesterone and relaxin relative to pregnancy in association with successful live births and still born calves.
Marine Mammal/Conservation Benefit: Increased understanding of the role of these hormones in the maintenance and success of pregnancies
Characterization of Urine Concentrations of Relaxin and Progesterone during Pregnancy and the Periparturient Period in Bottlenose Dolphins (Tursiops truncatus)
Project Investigators: Steinetz, B. G., Bergfelt, D. R., Adams, G. P., West, K., Brown J.
Affiliate Organizations: US Environmental Protection Agency, Washington DC; University of Saskatchewan; New York University School of Medicine; Hawaii Pacific University; Smithsonian Institution’s Conservation Research Center
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2010
Project Description: To analyze the hormones relaxin and progesterone in dolphin urine, relative to dolphin pregnancies. Archived and fresh-collected Dolphin Quest serum and tissue samples play a key role in making this new study possible.
Marine Mammal/Conservation Benefit:
- Increased understanding of the role of these hormones in the maintenance and success of pregnancies
- If criteria can be established, collecting dolphin urines may become an alternative in monitoring dolphin pregnancies through hormone evaluations.
Temporal Relationship Between Relaxin and Progesterone Throughout Pregnancy and Early Post-partum in Bottlenose Dolphins (Tursiops truncatus) with Live and Still-Born Calves
Project Investigators: Bergfelt, D. Steinetz, B., Lasano, S., Michelle Campbell, West, Kristi., Adams, G. P.
Affiliate Organizations: US Environmental Protection Agency, Washington DC; New York University School of Medicine; Hawaii Pacific University; University of Saskatchewan
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2010-2011
Project Description: The novelty of the study established a heterologous relaxin RIA for use with dolphin serum and placental tissue, characterized the temporal and differential changes in circulating concentrations of relaxin and progesterone throughout pregnancy and early post-partum and provided evidence that the placenta is a source of relaxin and progesterone in pregnant bottlenose dolphins.
Marine Mammal/Conservation Benefit: Increased understanding of the role of these hormones in the maintenance and success of pregnancies
Development and Implementation of a Method for Measuring Relaxin in Dolphin Urine for the Purpose of Identifying Early Pregnancy in These Mammals
Project Investigators: Kristi West
Affiliate Organizations: New York University School of Medicine; Nelson Institute of Environmental Medicine, NY; Conservation Research Center; Smithsonian Institution; Hawaii Pacific University
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2010
Project Description: This project is to develop and implement a method to measure the hormone relaxin in dolphin urine samples for the purpose of identifying early pregnancy in dolphins
Marine Mammal/Conservation Benefit: Increased understanding of the role of these hormones in the maintenance and success of pregnancies
Does ‘Carrying’ a Dolphin Calf in Infant Position Lower the Swimming Performance of Dolphin Mothers?
Project Investigators: Shawn Noren Kramer
Affiliate Organizations: Center of Ocean Health, Santa Cruz, CA
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Support: 2011
Project Description: The impact of infant position swimming on maternal swim performance has yet to be quantified. Understanding the effect of infant position on maternal swimming capabilities is important because:
- Infant position is one of the dominant positions maintained by cetacean calves during the first year of life
- This is the dominant position observed when calves are startled or tired, as might occur during a fishery interaction. If infant position swimming reduces maternal swim speed and distance covered per stroke, then there may be consequences for mother-calf pairs traveling at high swim speeds during tuna purse-seine fishery induced chases.
Marine Mammal/Conservation Benefit:
- Adds to the existing base of scientific knowledge
- Important for decisions regarding the policies for the dolphin chases associated with the activities of the tuna purse-seine fishery
- Potential application to limit animal mortality associated with purse-seine fisheries
Artificial Insemination
Project Investigators: Holly Muraco, Jay Sweeney, Rae Stone, Michelle Campbell
Affiliate Organizations: Six Flags, Dolphin Quest
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2012-2013
Project Description: Artificial insemination (AI) was planned with dolphins located at Dolphin Quest. This project involved monthly monitoring of bottlenose dolphins who were pregnant due to successful artificial insemination. This included fetal growth data, urine samples and hormone tracking.
Marine Mammal/Conservation Benefit:
- Successful Artificial insemination could offer an alternative the need for cooperative breeding loans of animals between facilities
- Increased genetic diversity of human care population
- Development of Artificial Insemination techniques that could be applied with other marine mammal species
Characterization of Stress-Related Corticosteroids in Urine Associated with Pregnancy and Pregnancy Loss and Correlation Between Corticosteroids in Urine and Blow
Project Investigator: Kristi West
Affiliate Organization: Hawaii Pacific University
Species: Bottlenose dolphins (Tursiops truncatus)
Dolphin Quest Supported: 2014
Project Description:
- To study stress-related hormones during pregnancy in dolphins under human care
- To establish if an increase in corticosteroids is a major factor in abortions and stillbirths
Conservation Benefit: This project will investigate if stress influences pregnancy outcome in dolphins, which will provide insight into the population impacts of environmental stressors on wild dolphins. The project will also aim to validate a non-invasive technique for measuring stress hormones that could be used to evaluate physiological stress in wild dolphins exposed to varying types and degrees of environmental stressors.
The Bottlenose Dolphin as a Model to Develop Methodology and Reference Hormonal Data to Analyze and Interpret Cortisol in Blow and Blubber Samples from Wild Cetaceans
Project Investigators: Kristi West, David Horgen, Don Bergfelt, Robin Baird
Affiliate Organizations: Hawaii Pacific University, Ross University, Cascadia Research Collective
Species: Bottlenose dolphin (Tursiops truncatus)
Dolphin Quest Supported: 2015
Project Description: The proposed projects aim to build upon recent progress by the research team to characterize stress-related hormones during pregnancy in bottlenose dolphins in human care and to develop alternative methods to collect and analyze samples to investigate the impact of environmental stressors on populations of wild dolphins and other cetaceans.
Marine Mammal Benefit/Conservation Benefit: By using these methods in a controlled environment, they establish important information for the species that can be used to investigate the impact in wild dolphins and other cetaceans.