Caring for Stranded Marine Animals
                                              Donate Now!

STEM: S is for Science

To define science or to explain what it is can be very challenging. Mirriam-Webster Dictionary provides multiple definitions but I think the most fitting is as follows… “Science: knowledge or a system of knowledge covering general truths or the operation of general laws especially as obtained and tested through scientific method”. The scientific method guides even the youngest of curious minds through the steps of observing something (a phenomena), developing a hypothesis and predictions, implementing testing methods, data collection, and development of a conclusion that can be further influenced by continual re-testing, additional data, and peer collaboration. Basically… science happens when we notice something new, cool, or unique and decide to study it further and discover the who, what, why, when, where, and how about it.

Around the world and at the National Marine Life Center, many scientists are interested in studying marine life so that we can better protect the ocean and understand the creatures that live there. In many cases, by studying the health of the ocean and marine animals, we can also learn about human health.

Over the past few years, NMLC has had a particular interest in seals experiencing a condition known as otitis media, or an inner ear infection, that can produce a rupturing of the eardrum. Otitis media is diagnosed after observance of discharge from the ear(s) followed by a swab sample of the discharge that might show bacteria and/or yeast. If the discharge sample shows bacteria and yeast a canalography will be performed. A canalography is a radiograph (x-ray) taken of the skull to show the inner ear and the status of the ear drum. A dye is put into the ear that is visible on the radiograph; by looking at the path of the dye the veterinarian can determine if the ear drum has ruptured or not. A ruptured ear drum indicated otitis media.

Samples are collected using sterile cotton tip swabs. To confirm the presence of otitis media, a sample of the ear discharge is taken and examined under a microscope so that particular bacteria and yeasts can be identified.

Ear discharge caused by otitis media is often whitish in color because of the presence of yeast and bacteria. Here you can see the entrance to the inner ear of Jones. Seals do not have an external ear flap.

Dr. Rogers and animal care team assistant Gabriella examining Jones’s canalography.

We have had multiple patients admitted to our hospital experiencing chronic cases of otitis media, including two of our summer 2018 pups, Jones and Bear. Both harbor seals experienced left otitis media and underwent extensive treatments in an effort to resolve the infection and heal the rupture. Treatments included ear saline flushings as well as oral, injectable, and topical antibiotics. After several intensive months of treatment another canalography was done. Jones’s canalography confirmed a persistent left ruptured eardrum. Unfortunately, further medical treatment was unlikely to result in the healing of the eardrum. Bear’s canalography indicated a possible healing of the tympanic membrane. It was decided that Jones and Bear would be fitted with a satellite tag. Satellite tags provide the opportunity to observe behavior of animals from a distance and to distinguish normal and abnormal habits. In this case the National Marine Life Center and associated scientists were interested in observing patterns of movement around the region as well as diving ability.

Harbor seal weanling Jones gives the photographer his best smile while on the exam and radiograph table. Jones is about to have his 1st radiograph since re-stranding after he was released post treatment for otitis media.

Jones proved to be an especially interesting case study in this respect. His satellite transmitted for about 3 months, displaying relatively normal dive depths and lengths. Jones did unfortunately find himself stranded for a second time in Maine, eventually making it back to our facility for his second round of rehabilitation. It is most likely that Jones re-stranded because of new health problems including parasites and pneumonia, not because of his otitis media. After treating the parasites and pneumonia , Jones received one last canalography. This time, it indicated a possible healing of the tympanic membrane or some material that was sufficient enough to cause a fluid barrier in the ear canal. He was approved for release, still having his satellite tag. Data was transmitted for another two months after release, yet again displaying normal behavior. Most recently Jones has been spotted hanging around at a Grey Seal haul out thanks to his flipper tag and his satellite tag has since stopped transponding; batteries don’t last forever.

Bear was also released with a satellite tag. That tag transmitted for approximately 4 months, allowing us to record location, dive depth, and dive length. Our understanding, based on the data collected, is that her behavior was in trend with Jones. We have no reason to believe that her diving behavior was altered or that she was unable to thrive in the wild because of otitis media.

Though these animals are cared for in a rehabilitation capacity, they are also serving as models for the rest of the wild population. Having these models allow us to study this disease, and numerous others, while obtaining a better understanding of how pathogens can affect an individual’s behaviors and overall survival rate. The post-release data collected from both Jones and Bear, via satellite tags, provided evidence that they were not affected by this disease in a way that prevented diving and hunting for prey in a normal manner. Though this data is vital to our study, it is far from completion. Our goal is to rehabilitate several more seals, under the same conditions as Jones and Bear, and to monitor their post-release data with satellite tags to see whether or not there is a common trend and how it fits into the wild population.

Science starts at the National Marine Life Center.

2 Comments

  1. Thanks for your feedback, Jeanne! 🙂

  2. Very informative article. Explains what NMLC does to help marine life .

Leave a Comment

Your email address will not be published. Required fields are marked *