Southern Right Whales

Its not such a surprise that a whale species that got its name from being slow, easy to catch and full of whale oil, still hasn’t recovered from hunting centuries ago.

They were once everywhere and in the Derwent people in colonial times complained about their noise and their inference with boat traffic. Then they were harpooned almost extinction in SE Australia.

While humpback numbers are booming despite a slow reproductive cycle, Southern Right whales are not in their old haunts in the sheltered bays of SE Australia. Aerial surveys across southern Australia indicated southern right whales are increasing in number in many places like the Great Australian Bight, but its not so noticeable in populated areas.

The south-east Australia population (Victoria, South Australia, Tasmania and New South Wales) appears not to have exhibited the same rate of increase, placing them in a more vulnerable situation. The South-western Australian population is currently estimated at 2,900 and the South-eastern population only 200 – 300 whales. It is estimated that 95% of the total Australian population over-winters at the head of the Great Australian Bight in South Australia. Thirteen Southern Right Whale coastal aggregation areas have been identified in Australia, three of which are in Victoria (Portland, Port Fairy/Warrnambool and Port Campbell/Peterborough).

The waters east of Warrnambool known as Logans Beach have proven to be a regular site where calving and rearing takes place. Females show a strong fidelity for frequenting calving sites. Whales can arrive from May onwards and females with young can remain in this nursery area up until October or early November.

Noisy boat traffic in places like the Derwent mean that the whales spotted were likely to be youngsters. The earlier slaughter of whales has generally resulted in daughters not returning to where their mothers and grandmothers had given birth…” it takes a long, long time for that behaviour to reappear, if at all,”.

Lactating females fast for at least four months while providing milk for calves. Southern Right Whales are not known to feed in Australian waters, their feeding grounds are further south (40-600 S) but rarely observed near the Antarctic pack-ice. They feed primarily on copepods and post-larvae of Munida gregaria and occasionally the larger Euphausia sp. krill, but are not considered to compete against other baleen whales for food.

The long term prognosis is worse. CSIRO researcher Dr Viv Tulloch says that modelling also shows that warming waters mean that they are likely to head in the other direction, “We are expecting they will start to decline again in the middle of this century, particularly in the pacific region …, so it’s not great news for them”.

Know your Southern Right Whale

Callosities (white lumps) appear naturally and are a characteristic feature on the heads of Southern Right Whales. The purpose of Callosities is not known. They are light grey in colour, appearing white against the dark skin of the whale.

Source http://whalespotter.com.au

Northern Right Whales on the Brink

Since the start of June, eight North Atlantic right whales — or 2 percent of the global population — have been found dead in Canadian water. Four of the whales were breeding females, of which fewer than 100 remain. The big issue is ship strikes.

“This is currently very clearly not sustainable,” said Philip Hamilton, a research scientist at the New England Aquarium in Boston. “At this rate, in 20 years, we’re going to have no more breeding females, and the population will be effectively extinct.”

Affected by hunting, which ceased in 1935, numbers rose, then fell again. In 2010, the population started declining Many pointed to a change in the whales’ migratory pattern in to areas in shipping lanes, possibly as a result of warming waters. As the whales’ usual feeding habitats have warmed, they theorize, the copepods that they like to eat have moved north. The whales followed.

Traditionally, the whales have spent the winter off Florida and Georgia, moved north to Cape Cod Bay in the spring and on to the Gulf of Maine and the Bay of Fundy for the summer. But in recent years, they’ve been appearing farther north, in the Gulf of St. Lawrence.

Researchers found that 88 percent of right whale deaths for which a cause was determined in the past 15 years were the result of either vessel strikes or entanglement. Seventeen North Atlantic right whales died in North America in 2017, including 12 in Canada.

The North Atlantic right whale, also known as the northern right whale or black right whale,

The Canadian government implemented measures including speed limits for certain vessels, a temporary ban on lobster and crab fishing in certain parts of the Gulf of St. Lawrence and increased aerial surveillance of the waters.

The restrictions were tightened in 2018 — and seemed to be working. Last year, no right whales were found dead in Canada. So officials relaxed them, to minimize the impact on industry. The relaxation has had a dramatic result.

Adult North Atlantic right whales average 13–16 m (43–52 ft) in length and weigh approximately 40,000 to 70,000 kg (44 to 77 short tons), they are slightly smaller on average than the North Pacific species. The third species of Right Whale is the Southern Right whale. The largest measured specimens have been 18.5 m (61 ft) longand 106,000 kg (234,000 lb).

Forty percent of a right whale’s body weight is blubber, which is of relatively low density. Consequently, unlike many other species of whale, dead right whales float.

There is little data on their life span, but it is believed to be at least fifty years, and some may live more than a century.