March 21 ~ March 28, 2015
Week Nine of our 25th Season
Lengthening days on the Silver Bank mark the return of Spring, and coincide with a stirring inside its cetacean visitors. Whales steeped in the warm waters of the tropics begin to consider the long journey home, back to the cold, nutrient-rich waters of the North. Although five to seven thousand humpbacks pass through the Silver Bank in a given winter, most will not stay the entire duration. Some arrive early and leave early, others arrive later or remain longer. Mothers with growing calves tend to be in this latter group, allowing the vulnerable young the best opportunity to gain strength and coordination.
Accordingly, this week’s in-water encounters are dominated by mother and calf pairs. In one instance, we enjoy multiple rounds with a sleeping mother and active calf, mama immobile below while her baby spins and splashes above. The demands of caring for an active, growing calf are extreme, and rest for humpback mothers is undoubtedly a rare and valued commodity (especially late in the season as baby gets more autonomous and therefore harder to manage). This mother appears oblivious to the humans floating quietly above, but another visitor nevertheless interrupts her nap: a large spotted eagle ray passing just over her head startles her into kicking off. Not for long though; she quickly settles again, granting us an extra hour in her presence. Another encounter with a mother, calf and escort trio also comes with a unique twist: a pod of curious dolphins materializes around the trio, weaving among and around their heads. Baby appears delighted, but escort less so: he tail slashes at the much smaller cetaceans as if their presence were a nuisance to him (it seems dolphins are like gnats to a grown whale: inconsequential and unacknowledged, except when they invade personal space). Unlike escort, we enjoy the dolphin presence for several minutes before they dart away again, high-pitched squeaks fading into the distance.
Other mother and calf encounters result in some fantastic surface activity this week. Babies grown strong on mother’s milk are showing off their skills now, and the effort is always exciting to watch. Multiple breach sequences by baby are frequent, with occasional demonstrations by mom as well. One baby breaches for nearly an hour, his growing coordination readily evident, as mom lazily fin slaps in the background.
Other surface activity is picking up as well: rowdy groups form frequently in late season as competition heightens for a dwindling number of estrous females. Like mothers with calves, lone males tend to linger on the Silver Bank, eager for a last chance to contribute their genes to the next generation. We are witness to several different rowdy groups in our first 24 hours this week, and another to finish off the week. The early rowdy group encounters this week exemplify grace more than violence: rows of arcing backs streaming with water, turquoise pec fins gliding just below the surface. The last group is more violent: bloody tubercles and dorsal fins testament to the heated nature of this battle. Nature has established the imperative to mate, and these males are certainly answering the call.
A last encounter with a singer completes a varied week. Like several before him this season, this male pauses head down in the water column, perhaps the better to project his mournful-sounding song. Seemingly unlike the others, though, this singer includes a number of extremely prolonged squeals. All humpbacks in a given population sing the same song, though it does evolve throughout the year; perhaps this individual is adding his own unique twist to the template.
Another varied week on the Silver Bank, and another week of beautiful sunny days and starry nights!
Written by: Lisa LaPointe, Aquatic Adventures
Designed by: Heather Reser, Aquatic Adventures