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We just had our last day of our field season. It was an amazing day, our best yet in terms of numbers of whales! We saw 24 whales total, and it likely would have been more had we not had to leave early to make the trip up the estuary and back to port. It was a highly successful field season. We surveyed over 1400 miles, saw over 250 whales, and collected photo-identifications of around 80 individuals! We also collected song recordings, skin samples to be used for genetic analysis (from sloughed skin of active whales) and took literally thousands of photographs. We would like to thank The Moore Foundation, the Islas Secas and several anonymous donors for their support of our research. And thanks to everyone who read the blog! We hope to be back next year! 
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Humpback whales are known for the songs they sing…I’m sure you’ve heard it before on a tv commercial for insurance or in some new age soundtrack. These are true “songs,” with themes and phrases that are repeated in a specific order. Only the males sing, and they sing primarily during mating season. Interestingly, all the animals in the same population sing the same song, kind of like their own dialect. Other populations sing different songs. We have a hydrophone (underwater microphone) with us and throughout our field day we periodically listen for whale song. Sometimes we don’t even need the hydrophone. On many occasions this year we’ve had singers right underneath us, and the sound is amplified by the hull of the boat. It is an amazing experience to hear these animals sing right beneath you and have the sound reverberate throughout the boat. Here is a recording we made this year of a whale right beneath the boat. There are other whales in the background singing as well…can you hear them? There’s even a few high frequency dolphin whistles in there too. Here is a picture of the whale singing in the recording. It suddenly stopped singing, and then breached twice in front of us. Notice it's just starting to blow out of its blowhole.  The singer begins a breach out of the water Here are some more species that we have seen, both on land and at sea: These sea snakes (Pelamis platura) are the most widely distributed of all the sea snake species. We very often see a few every day. They are known to be highly venomous, although their mouths are too small to bite a human. 
Yellow-bellied sea snake
Here is a sailfish jumping right near two humpback whales. 
Sailfish and humpback whales
Here is a closer shot of that same sailfish... 
Sailfish!
Here is one I was really excited about....this is a Hawksbill sea turtle (Eretmochelys imbricata). I have never seen one before and I was thrilled that it stayed at the surface for a while giving me a chance to take some photos. They are critically endangered and historically have been hunted for their beautiful shell. 
Hawksbill sea turtle
This juvenile common black hawk (Buteogallus anthracinusis) is often near the dock in the morning when we leave. 
Juvenile common black hawk
Here is the adult version of the same species. 
Common black hawk, adult
This boa was outside my bedroom window yesterday morning! 
Boa constrictor
Here are some of the seabird species we most commonly see. Thanks to Hannah, Josh and Sophie for confirming some of the species! 
Brown pelican
Brown noddy
A blue footed booby and a brown booby share a log
Brown boobies
Black tern in winter plumage
Storm petrel (probably a Band rumped storm petrel)
Frigate birds
Red necked phalaropes (in winter plumage)
This is one of my favorites from yesterday. Mom is on her side with her belly facing us and her pectoral fin in the air. The calf is just starting to emerge from the water getting ready to do a breach. 
Photo by K. Rasmussen
Every day we see moms and calves, almost 50% of the groups we see contain a calf. Sometimes these calves will approach our boat with curiosity. If they do this, we will sit with our engines in neutral and wait and see what happens. Many times they will pass by once and then mom herds them away, but sometimes they will stay for a visit. Today we had a small calf come very close and circle several times. Mom was nowhere to be seen, but we knew she was VERY close, just not surfacing. Here is a picture of the calf’s head. My captain said “parece un dinosaurio” “it looks like a dinosaur”. Those bumps on the head are called "tubercles", and are characteristic of humpback whales. 
The head of the calf as it approaches our boat
After a few minutes, mom finally surfaced underneath the calf and supported the calf on her head. She is just below the surface of the water. 
Calf resting on top of mom's head
Then the calf started to roll around on its back. Here is a picture of the calf on its back, belly up with its pectoral flipper in the air. Can you see where the eye is? 
The calf with its belly up still on mom's head
 Eye of the calf Here is that same photo zoomed in on the eye. It seems like the whale is looking right at us! These are definitely curious animals. Finally after about five minutes of this, mom and calf left and the next time we saw them they were several hundred meters away. They seemed to be done with us, so we left them on their way and went to look for more whales.
Photo by K. Rasmussen
Today we saw a giant splash in the distance…there’s only one thing that makes such a big splash… a breaching whale! As we approached, we saw that it was a calf breaching over and over again. I had my camera ready and suddenly the mom breached at the exact same time as the calf! I have never seen them breach together before, and I was lucky to get a shot. They both continued to breach, but never again at the same time. It was a lovely moment!
 One of our main objectives for this project is to collect photo-identifications of the tail flukes of humpback whales. Each whale has unique markings on the undersides of their flukes, and these can be used to recognize individuals. We share our photo-ids with researchers in other areas to determine which whales we have both seen, which gives us some information about their migration routes. Whales photographed off Panama between July and October have also been seen in Costa Rica, Colombia, Ecuador, Chile and Antarctica. You can also estimate the population size based on how many whales you have seen in previous years and how many whales are new that year. Here is an example of an id photo. In order to photograph the underside of the tail, you need to be behind the whale as it dives, which is not always easy! To make it even more difficult, whales do not always raise their tails when they dive. Many times the whales we are following never raise their tails. Sometimes we have to get creative with our fluke ids. This whale was on its back, raising its tail over and over and slapping it down on the water. 
It was showing us the underside of the tail, but upside down! 
We inverted the photo, and now it is usable as a photo-id. 
A few days ago one of our engines started overheating. After troubleshooting a few things, we realized something had happened to the impeller and it was no longer pumping cooling water to the engine. Luckily, we have two engines and we limped home using one of them at 7 knots (we usually travel between 15-20 knots). It is not easy to get parts here in Panama. Even the sparkplugs we need I have to bring from the states. As luck would have it, a mechanic happened to be coming to the islands where we are staying and was able to bring the parts we needed and helped us fix the engine. Thank you Isla Secas and Luigi for helping to get us back on our way!  The mechanic uses his laptop to diagnose the engine problem  The artistically talented Betzi Perez drew this cartoon based on what we saw a few days ago while watching a competitive group of whales. There were two boobies (one blue footed and one brown) sitting on a log very near all the activity. We were amazed that the birds did not fly away despite these giant animals crashing nearby. Nice work Betzi! 
Cartoon by Betzi
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AuthorKristen Rasmussen Archives
September 2012
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