One needs only to look at her right side to understand how this fin whale got her name. Zipper bears an enormous zipper-shaped scar, the result of a collision with the propeller of a ship. This fin whale also has a very pronounced scar on each side of her peduncle. On the other hand, her dorsal fin has no notches and her chevron shows little contrast.
Observers recall their first encounter with Zipper in 1994, when she was covered with fresh wounds and still ragged-looking skin. This type of injury is characteristic of a collision with a boat propeller.
Zipper survived her lacerations and continues to visit the Estuary. Her large scar reminds us that collisions between boats and marine mammals can be fatal. The vigilance of commercial and recreational boat operators, as well as compliance with the regulations of the Saguenay-St. Lawrence Marine Park (speed limits and minimum observation distances) make it possible to mitigate this risk, which becomes more acute in foggy weather or in heavily visited feeding areas.
Prior to 1994, Zipper was likely a seasonal resident of the Estuary; however, since she did not have any distinctive traits at the time, she had yet to be identified.
Zipper is just as well known in the Gulf as she is in the Estuary, which she visits regularly. She has been photographed 15 times since 1994, including GREMM’s first snapshot of her in 2007. Zipper has also been seen with two calves.
From the newsletter Whale Portraits, August 2, 2018, by Camille Bégin Marchand
Zipper and scar evolution
Zipper is a fin whale easily recognizable by her obvious, zipper-like scar on her right side. Her peduncle also bears clearly visible markings on either side. Her dorsal fin has two small notches and her chevron shows little contrast. In 1994, the year of her first photo-identification, this fin whale arrived in the Estuary covered with fresh wounds and ragged skin. A collision with a boat left her in this state.
A biopsy taken in 1999 helped confirm her sex: Zipper is a female. In fact, she has since had two calves (2001 and 2007). Although she was first identified in 1994, her previous visits may have gone unnoticed because of the absence of any conspicuous traits. Zipper is also well known in the Gulf of St. Lawrence, where she has been photographed numerous times since 1994.
The scars and markings of individuals visiting the Estuary evolve over time. The broad, deep scar on Zipper’s right flank has changed since her accident. The skin of cetaceans is smooth, taught and hairless, and is in contact with a marine environment where the water is salty and sometimes very cold. Despite this, it seems that scarring and healing times of cetacean wounds are comparable to those of land mammals. The process is very effective, however. Dolphin studies in both temperate and cold waters have observed the formation of a protective buffer made of degenerative cells that, when in contact with salt water, protect the wound, allowing for easier healing of the underlying tissues and closing of the wound. Unlike land mammals, there is no formation of a sort of crust or scab.
In cetaceans, salt water seems to play a role in the scarring process. Injuries inflicted by sharks or other individuals of the same species form scars that disappear after 7 to 8 months. Broader, deeper scars create deformations and pigmentation changes that seem to be permanent. A study on scarring in pilot whales has demonstrated that in less than a year, wounds caused by biopsies are closed and the healing process is complete.
Sources (for Whales Online)
Bloom, P., & M. Jager (1994). The injury and subsequent healing of a serious propeller strike to a wild bottlenose dolphin (Tursiops truncatus) resident in cold waters off the Northumberland coast of England. Aquatic Mammals, 20, 59-59.
Bruce-Allen, L.J., & J.R. Geraci (1985). Wound healing in the bottlenose dolphin (Tursiops truncatus). Canadian Journal of Fisheries and Aquatic Sciences, 42(2), 216-228.
Corkeron, P.J., R.J. Morris, & M.M. Bryden (1987). A note on healing of large wounds in bottlenose dolphins, Tursiops truncatus. Aquatic Mammals, 13(3), 96-98.
Giménez, J., R. De Stephanis, P. Gauffier, R. Esteban, & P. Verborgh (2011). Biopsy wound healing in long-finned pilot whales (Globicephala melas). The Veterinary Record, 168(4), 101.