Archive for the 'Dolphins' Category



A Blue View: Rising Seas

A Blue View is a weekly perspective on the life aquatic, hosted by National Aquarium CEO John Racanelli.

From the smallest plants and animals invisible to the human eye to entire ecosystems, every living thing depends on and is intricately linked by water.

Tune in to 88.1 WYPR every Tuesday at 5:45 pm as John brings to the surface important issues and fascinating discoveries making waves in the world today.

June 26, 2013: Rising Seas

A Blue View podcast

Click here to listen to John discuss the impact
climate change is having on rising sea levels. 

On these hot summer days, our thoughts tend toward ice cream cones and tall glasses of ice water on a sweltering afternoon rather than the melting of ice sheets around the world. But just as the ice melting in your glass causes the water level to rise, so too does the melting of the world’s ice shelves.

Perhaps you’ve seen the incredible videos of massive chunks of ice breaking away from a glacier, causing crashing impressively into the sea. Until recently, it was thought that this was the primary cause of ice loss in Antarctica. But in fact, a study by NASA and university researchers indicates that warming oceans are also dissolving the ice from underneath the ice shelf at unprecedented rates, causing the greatest loss of Antarctic ice shelf mass. Scientists plan to use these data to help determine how ice shelves melt, improving projections of how the ice sheet might respond to a warming ocean and contribute to sea level rise.

Ice loss is not just occurring at the poles: NASA researchers have discovered that glaciers outside of the ice sheets of Greenland and Antarctica lost an average of 571 trillion pounds of mass each year during the six-year study period, causing sea levels to rise almost two-tenths of an inch during that time. This actually matches the sea level rise attributed to the combined ice loss of the Greenland and Antarctica ice sheets.

Ice melting isn’t the only contributor to sea level rise. Warming temperatures cause waters to warm and expand. In turn, warming waters take up more volume. This phenomenon is called thermal expansion. The combination of ice melting and thermal expansion means that sea level rise is not just a possibility…it is happening now, and the only question is how fast it’s going to rise.

Many scientists now believe that sea levels will rise by no less than one to two feet by 2100. And without dramatic reductions of greenhouse gas emissions, the threat could be much more substantial.

The East Coast in particular is at greater risk from sea level than other areas of the world, mainly due to ocean currents and differences in seawater temperature and ocean salinity, according to climate scientists. The U.S. Geological Survey found that sea levels from North Carolina to Boston climbed by about 2 to 4 millimeters a year between 1950 and 2009 as compared to a global average of one-half to 1 millimeter.

These amounts may seem small and unimportant, but the repercussions from these rising levels are anything but. Imagine increased coastal flooding, shoreline erosion, loss of wetlands, and destroyed homes and businesses on the order of superstorm Sandy. Sea level rise does affect us all.

We need to take steps to control warming, as sea surface temperature and sea level rise are inextricably linked. According to the EPA, sea surface temperatures have risen at an average rate of 13 one-hundredths of a degree per decade since 1901. As small as that may sound, over 112 years, that’s an increase of one and a half degrees, which is already impacting not only sea level, but also coral reefs and other essential ocean habitats, migration and breeding patterns, the intensity of storms, and the spread of invasive species and marine diseases.

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A Blue View: Dolphin Earthquake Study

A Blue View is a weekly perspective on the life aquatic, hosted by National Aquarium CEO John Racanelli.

From the smallest plants and animals invisible to the human eye to entire ecosystems, every living thing depends on and is intricately linked by water.

Tune in to 88.1 WYPR every Tuesday at 5:45 pm as John brings to the surface important issues and fascinating discoveries making waves in the world today.

June 19, 2013: Dolphin Earthquake Study

A Blue View podcast

Click here to listen to Dr. Mark Turner discuss how
our dolphins reacted to last year’s earthquake.

On August 23, 2011, a magnitude 5.8 earthquake occurred with its epicenter approximately 118 miles from the National Aquarium, Baltimore. A short time before the dolphin pavilion started shaking from the earthquake, an Aquarium volunteer logging the activities of four dolphins noticed that they all started to swim very quickly in close formation, something she could not recall ever having seen before. She had enough time to note this behavior in her handwritten log before the building suddenly started shaking. At the same time all this was happening, the underwater sounds in the dolphin pools were being recorded using a pair of hydrophones (i.e., underwater microphones). The combination of the in-person observation and the hydrophone recordings provides valuable insight into dolphin behavior.

When an earthquake occurs, seismic waves radiate out from the focus of the earthquake at different velocities. The fastest of these, called the primary wave or P-wave, can travel at speeds of 15,000 miles per hour. However, although very fast, P-waves often are unnoticed by humans. The S-wave and surface waves, the ones that shake everything and cause the worst destruction, travel at much slower speeds.

Although no humans at the Aquarium that day reported feeling the P-wave, its trace did show up in our hydrophone recordings almost 22 seconds before the arrival of the S and surface waves. In view of the P-wave’s appearance in the recordings and the dolphins’ behavior, marine mammal researcher Mark Turner believes the dolphins felt the P-wave, and the volunteer observed their reaction to it. Listen to the hydrophone’s recording: 

This is a clip of the underwater sounds in the dolphin pools when the August 23, 2011, Virginia earthquake occurred. Two hydrophones were recording at the time. The left stereo channel is the recording from the hydrophone in the front pool where a dolphin presentation was in progress. The right channel is from the back holding pool where fast swimming in an unusual configuration was observed. In the video that accompanies the sound clip, the top two panels show the raw signal picked up by each hydrophone. The top panel is from the front pool and the bottom one is from the holding pool.

The bottom two panels are spectrograms. A spectrogram is a visual representation of sounds in which the x-axis is time and the y-axis is frequency. In a spectrogram a dolphin whistle will appear as a dark, wavy line, and a squawk can sometimes appear as a stack of parallel wavy lines.

The sound clip begins at almost exactly the time the earthquake started in VA. The various seismic waves traveled from the earthquake’s focus to Baltimore at different velocities, with the P-wave arriving first, 27 seconds into the clip. Although the very low frequency vibrations induced by the P-wave are visible in the upper panels, they are inaudible, although you might hear some water splashing. The S and surface waves (the ones that are very loud and shook everything) did not arrive until almost 22 seconds later, 49 seconds after the beginning of the clip.

You may hear some of the presentation music, a bit louder in the left channel. If you listen carefully you will also hear (and see in the spectrograms) dolphin clicks, squawks and whistles. And, of course, you will hear the loud noises made by the earthquake surface waves as they sounded underwater.

An excellent overview of the different seismic waves with animations can be found by clicking here.

All signal displays were generated using Raven Pro, Interactive Sound Analysis Software, Bioacoustic Research Program at the Cornell Lab of Ornithology.

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So You Want To Be a Marine Mammal Specialist…

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The most common question our team is asked is how to become a dolphin trainer. For me, being a dolphin trainer was a childhood dream, so I geared my education and experience toward achieving this goal at a young age. Growing up in Chicago, I attended many lectures and visited both the Shedd Aquarium and Brookfield Zoo as often as I could. After high school, I participated in a volunteer program for a summer at a research facility in Hawaii, which only solidified my dreams and allowed me to understand further the path I needed to take.

The most important advice I can give someone who has the desire to join our incredible team is to understand that this is not a 9-to-5 job; it is a lifestyle. I can turn my computer off when I leave for the day, but of course cannot do the same with the animals. Any applicant must be willing to work weekends, various shifts and even holidays as animals do not take holidays and snow days off!

national aquarium dolphins

We spend a lot of time with our dolphins every day of the week, bonding with them, training new behaviors and doing presentations for our visitors!

First, the basics: It is recommended to have a degree in psychology (we work with the animals using operant condition), biology (so there is a basic understanding of anatomy and physiology) or zoology (the study of animals). Also, participating in internships provides hands-on experience (like the ones we have here at the National Aquarium) and are great ways to get a glimpse into the field, make connections and gain practical skills. One must also be a comfortable swimmer and typically be scuba certified.

With the basics covered, moving into the field can be a challenge. The field is very competitive, and there are not as many opportunities due to the number of facilities in the country. Being willing to move around and to keep options open will definitely help to broaden the field opportunities.

Each facility is structured differently. In general, however, the amount of experience will directly correlate to the level of responsibility and opportunity (as with any career choice). Here at the National Aquarium, we have aides, assistant trainers, trainers, and senior trainers. Moving from one level to the next takes dedication, experience and time. A typical day begins at 6:30 am, when we sort through hundreds of pounds a fish in order to make up the animals diets.

national aquarium dolphin staff sorting fish

Throughout the day, we participate in public presentations, various training and play sessions as well as research and enrichment studies. Sounds glamorous and fun, right? Unfortunately, that is just half the day. The rest is filled with cleaning, making and washing fish buckets, diving to clean the habitat and a lot of record-keeping.

Being in the animal field is incredible and extremely rewarding, but it is not without sacrifices, hard work and dedication. Got a question about my job? Ask me in the comments section! 

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Happy Birthday, Jade!

National Aquarium is celebrating a very special birthday today! Jade, one of our female dolphins, born on May 22, 1999, is 14 years old today!

atlantic bottlenose dolphin

About Jade

Gender: Female

Weight: 400 pounds

atlantic bottlenose dolphin

Jade eats about 22 pounds of fish per day!

Family Tree: Daughter of Tanya (dam) and Lester (sire), mom to Foster!

How to Recognize Her: Jade has a slightly ruffled dorsal fin that leans slightly to the right. She also has a long rostrum with a very pronounced underbite.

Trainer’s Note: Jade is a very fast learner and has even invented her own behaviors!

atlantic bottlenose dolphins

Jade showing off her high-flying skills!

Stop by today to see Jade! Can’t come wish Jade a Happy Birthday in person? Leave her a message on our Facebook page

Happy Birthday, Maya!

National Aquarium is celebrating a very special birthday today! Born at the Aquarium on May 13, 2001, Maya, one of our female dolphins, is 12 years old today!

Atlantic bottlenose dolphin

About Maya

Gender: Female

Weight: 420 pounds

To stay healthy and happy, Maya and our other dolphins  are fed a healthy diet of fresh fish and given routine vitamins!

To stay healthy and happy, Maya and our other dolphins are fed a quality diet of fresh fish and given routine vitamins!

Family Tree: Daughter of Shiloh (dam) and Nalu (sire)

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Maya as a calf!

How to Recognize Her: Maya is lighter in color, with a light-tipped rostrum and a very pink belly!

Trainer’s Note: Maya likes to spend a lot of her time with her half-sister Chesapeake and is very playful. She loves to show off her “fast-surfing behavior” for both the trainers and our guests!

Stop by today to see Maya play around with her sister Chesapeake! Can’t come wish her a happy birthday in person? Leave Maya a message on our Facebook page


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