Second Quarter Dolphin Report… and More!

July ended and another quarter of this year is in the books! The study team on board the Dolphin Explorer collected data about our local dolphins on 128 excursions from April 1st through July 31st with some new findings. 2,126 sightings of the 130 local, residential dolphins were recorded, making an average of 16 of these mammals per trip.

In the past 3 + years the average has been 11 to 12 dolphin sightings during each and every quarter over 1,416 excursions. This is an increase of nearly 50% more dolphins per trip this past quarter. The dolphins sighted were not new to the area, but the population that we have known for years, just more of them per trip. The team will document if this trend stays consistent and why sightings have increased, if it is short-term or over a longer period.

Our dolphin population is doing quite well. All of the surviving calves born in the Fall of 2022 are doing well and getting ready to celebrate their first birthdays over the next few months. This is good news that our ecosystem is healthy, and moms are taking great care of their young, providing plenty of milk for them. 

Also, a small number of our calves are reaching the age of three this Fall. Most calves stay with the mom for three years, learning where to feed, what to catch and also creating some social skills. By this age they have learned all they can from mom, and she will send them on their own path, especially if mom is pregnant.

A new calf depends on the mother’s milk for about two years. The young will start fishing at just a few months old, mimicking mom’s behavior and learning how to forage. When mom stops nursing the calf, at about two, mom could be in a mood to become pregnant again. With a one-year gestation period, a new calf would be born when the existing one turns three years old, and that one would leave mom’s side.

In July, we noted that two calves have left moms’ sides at just 33-34 months old, a strong indication that these moms will give birth within the next few months. There will be a few more youngsters departing from mom in the next month or two, all ready to experience a life independent of parental help.

Our adult female population is thriving. Survival rate is 100% over the past 12 months. The team has noted that as many as 15 females could give birth this Fall. It is not likely that all of them will, but it is also likely that a few of our younger females have reached maturity and may surprise the team with their first babies! 13 new calves would increase our residential population by 10%, something that we rarely experience, year over year.

The adult males are doing great. Of the 15 adult guys in the area, six of them are very dominant when it comes to being the “kings of the jungle” and fending off the younger adult males, especially when it comes to chasing the girls around! However, a few of these young men are growing stronger and could challenge some of the long-standing males for a chance to move up the ranks. Some of the dominant males have been at the top for 15 to 20 years and may be getting older and slower. Our team will watch this development.

There will be some calves that left moms’ sides reaching maturity this Fall. Females typically become physically and sexually mature at about seven to 10 years old in our area, while the males mature at about 12 years old or later. The team will note which dolphins are jumping up in rank and how their behavior patterns might change. 

Overall, our population is growing and doing well. It is important to note that, in addition to our 130 resident dolphins, there are others that pass through our study area. Dolphins are identified by markings on their dorsal fins, that fin on their back you see when they surface to breathe, and we have more than 200 photos of these fin pictures of “transient” dolphins, ones that just pass through or visit for a short while.

The team will continue to document as much as we see and keep the public informed. Our information does not go unnoticed since we send quarterly reports to colleges and other marine study programs around the world. These studies for 2024 are now available for public viewing on our website. You can go to dolphin-study.com and go to the tab that says “More.” Click on that and go to “News” to read a detailed report of our observations.

You can also contact us on that website to make a reservation and join us for an excursion. Birthing season is approaching, and times on the water are very exciting! Until next time, thanks for reading!