Here come those Males!
By Lloyd Edwards

1. News

On our last cruise, we saw something very special. We were completely surrounded by ten very active and “excited” humpback whales.

I started to explain to our customers that it was typical male behavior during the winter season …. we can call it the “testosterone effect”!

One of the customers asked me how we can distinguish between males and females.

The answer is not easy. Physically, they are quite similar. In general, the females are a bit bigger than the males. But we can distinguish them from the behavior, especially during the breeding season.

That day we spotted a large group of males (around 10) moving quite fast, interacting with and teasing each other. If you look at the below images, you can see how fast they were moving by the way the water runs off their bodies.

That is typical male behavior during the breeding season, where the females are in “estrus” and the males have high levels of testosterone and sperm. This leads to a real chase by males, for solitary females or females with their calves.

During this chase, the male starts to compete against the rivals with very impressive, and sometimes quite aggressive threatening tactics. This includes slapping the water with the tail and pectoral fins as well as displaying incredible breaches.

Sometimes the threats aren’t enough, so they can have physical contact like head lunges, tail and flipper hits.

Another special behavior that happens during this season, is the males becoming professional singers! They can produce very complex songs which can have a different meaning. The concerts can last up to 30 min and travel for 10 km. The songs are still being studied and there is a discussion in the scientific world about why the males produce those songs. Some of the theories claim that it is to impress and to attract the females, while other theories claim that it is for announcing their presence and heading off the rivals. At this stage there is not enough evidence to prove either of them.

Another interesting observation was the interaction between the Indo-Pacific bottlenose dolphins and the Humpbacks. It went on for about twenty minutes and the dolphins would just not leave their distantly related cousins alone. Although we have seen this behaviour before, it is not all that common. It could be because both species are incredibly intelligent and therefore seek out interactions of this nature.

This Humpback male surfaces in front of Keith Gibbs, the skipper of Winkle. Taken with a Nikon Z9 mirrorless ISO 180, 200mm zoom, f6,3 and 1/1600th second. I forgot to check the settings so would have gone with a much smaller aperture!

These three males surprised us and popped up right in front of "My Bru". Normally we keep our permit distance of 50 metres, while allowing the whales to control the encounter if they come closer. In this case I slipped the engines into neutral and allowed the whales to head off.

I got the settings right here and changed the f stop to f 13 in order to increase the depth of field and get the background in focus. So cool to see these animals so close to our amazing Summerstrand Beachfront!

This is where the whales get their names. As can be seen, they arch their backs prior to a deep dive.

These three males surfaced off our port bow. Note how quickly the water is running off their flanks.

These Indo-Pacific bottlenose dolphins appear to be chasing this male Humpback.

A Humpback lies on his side slapping the water with his pectoral flipper while the bottlenose dolphins cruise past.