The Orcas & Herring Collection

About the Species

Orcas (killer whales) are a species accentuated by brilliance, dominance, and community. They are the most widely distributed and fastest marine mammal in the world. Killer whales are apex predators notorious for being some of the most remarkable ocean hunting connoisseurs however, hunting tactics, diet, and other biological features differ slightly among the different Orca populations or ‘ecotypes’, which are perhaps separate species.

Biology

Physical Traits

• Orcas, often misjudged as part of the whale family, are dolphins. They are the largest of the dolphin family, reaching up to nine metres in length and over 7,000 kilograms in weight.
• They have a unmistakable colouration, with clashing black and white patterns. Hence, their universal nickname of ‘sea-pandas’.
• Their large dorsal (top) fins extend from one to two metres, according to sex (males usually have double the dorsal fin height compared to females).

Reproduction and Lifespan

• Orcas reach maturity for females at about eight years old and for males at about twelve years old. The gestation period of a female is roughly 15-18 months, with a notably low survival rate (Orca calves have a 40% mortality rate).  
• There are no explicit seasons for birthing/breeding, although it is believed that females give birth every five years until they peculiarly undergo menopause at about the age of 40.
• Male and female Orcas have considerably different lifespans. While a male is thought to live an average of thirty years, a female has an standard life expectancy of fifty years.

Viability

Threats and Climate Change

• Orcas, the top predators of the ocean, are essential for retaining structure and function in marine ecosystems.
• Because they are top predators, they are susceptible to bio-magnification. Bio-magnification is the accumulation of harmful chemicals and pollutants that accumulate in organism tissues. The higher the predator is on the food chain, the more toxins are accumulated and exposed to the predator. Due to the rising ocean plastics, garbage, and non-biodegradable chemicals (such as PCBs), an Orca’s health (in terms of immunity, fertility, and development) will consequently be compromised in many unforeseen ways.
• Overfishing and depletion of prey stocks also threaten Orca populations, being that they rely on a large amount of stocks for food security.

Conservation Status

• It is estimated that there currently are about 50,000 Orcas worldwide. Although, there are three different ‘types’ of Orcas: Resident killer whales, Offshore killer whales, and Bigg’s or Transient killer whales.

• According to the IUCN, there is a data insufficiency on Orcas, especially due to the potential of differing species. Therefore, all Orca ecotypes (Resident, Transient, and Offshore), subspecies, and populations are considered threatened.
• Luckily, as opposed to the culling and over-harvesting in the past, Orcas are protected in most oceans today.

Current Research

• One killer whale query that remains unanswered is their particular adaptation of menopause. Besides a few other whale species, only humans are known to go through menopause. Scientists have grappled with determining why and recent studies hypothesise a few evolutionary benefits, such as ‘grandmothering’ (tending to the needs of offspring and grand-offspring to increase descendants fitness rather than breeding themselves).
• In recent behavioural research, scientists employed drones to observe orca pod behaviour. Recently, it was discovered that killer whales establish close ‘friendships’ within their pods. These friendships, like humans, are usually with those of the same sex and similar age.