Dolphin bow-riding in front of a cargo ship near JAXPORT

Bottlenose dolphins inhabiting the St. Johns River (SJR) are currently managed as part of the Jacksonville Estuarine System stock (population), which is considered a strategic stock by NOAA Fisheries because the loss of only a few individual dolphins could dramatically impact the sustainability of the population. These dolphins are currently at risk due to the high potential for anthropogenic (human) disturbance within this urban, industrial habitat. Cumulative impacts of multiple potential stressors (e.g., fisheries interactions, persistent biotoxin exposure, noise pollution, and port expansion) within the river may surpass the tolerance threshold for this population.

SJR dolphins may already be experiencing population disturbance. In 2010, an unusual mortality event (UME) was declared for SJR dolphins in response to 23 documented strandings/deaths, almost half of which were young calves. A UME working group (mandated by NOAA Fisheries) was unable to definitively determine the cause of the UME due to limited knowledge of this population at the time. SJR dolphins were again impacted by the large-scale 2013-2015 dolphin morbillivirus epidemic and UME along the Atlantic coast. Although this epidemic was initially assumed to be limited to coastal dolphins, at least seven SJR dolphins stranded and were morbillivirus positive.

 

Threats To Wild Dolphins 

Unfortunately, several St. Johns River dolphins are severely entangled in fishing gear and lines each year. Our research team plays an integral role in identifying entangled dolphins and assisting management agencies with rescue efforts. 

Our local dolphins are also impacted by things that are not easy to see or measure, like chemical and noise pollution, commercial and recreational boat traffic and coastal development. These anthropogenic or human-made changes to the environment affect the health, behavior and reproduction of dolphins.

mouth-entangled dolphin
Eros has fishing line wrapped around and cutting into his lower jaw. NOAA veterinarians have deemed this a life-threatening entanglement.
frisbee entangled calf
Aerobie (calf) was entangled in a hollow frisbee that was cutting into her throat, but our disentanglement effort was successful!

 

 

dolphin with skin lesions
Skin lesions are an indicator that a dolphin's immune system is compromised. We can track lesion prevalence over time as a non-invasive indicator of dolphin health.

 

What You Can Do To Help

  • Boat safely around dolphins – stay at least 50 yards from dolphins and put your engine in neutral when dolphins are near.
  • Don’t feed, touch or swim with wild dolphins.
  • Prevent pollution.
  • Support dolphin research.

Report Injured or Stranded Marine Animals
FWCC Hotline 1-888-404-FWCC (3922)

If you find a stranded dolphin, whale or manatee, please don't put animal safety above human safety. Do not push the animal back into the water. Please call professionally trained responders for help. If possible, wait with the animal until a trained responder returns your call.

The Do's and Don'ts when Viewing Dolphins in the Wild

Viewing dolphins in their natural habitat is an educational and enriching experience if done safely and responsibly. As human interactions with wild dolphins increase, the risk of disturbing or injuring them also increases. Visit NOAA's dolphin-watching guide for some important do’s and don’ts to remember when viewing dolphins. Help keep wild dolphins safe!