The Mighty Blue Whale

By Sarah Jones

The blue whale holds many records in the animal kingdom, and Canadians are lucky enough to have this breathtaking creature include our coastline in its distribution. While you can’t find the blue whale in your garden, the animal serves as a good example of how our gardening practices go a long way in benefitting the health of creatures all over Canada, including aquatic ones. Read on to find out some interesting facts about these animals and what you can do to help them.

With an average weight of 64,000 kilograms the blue whale is the largest animal to ever exist, far out-measuring even the largest dinosaurs. To put it into perspective, a blue whale weighs the same as approximately 30 to 40 African elephants! However, the whales range in size depending on which part of the world they live in. Whales found off the North American coast are slightly smaller on average than those found in southern waters. The whales found in Canada average 27 metres in length, the females being approximately one to three metres longer than their male counterparts. The blue whale can be found in the Laurentian Channel south of Newfoundland in March, before they travel to the St. Lawrence in April. It is thought that they spend most of May and June in Newfoundland before travelling all the way to Greenland and Iceland for the rest of of the summer.

The blue whale has one of the loudest and deepest calls in the animal kingdom. Their calls which, consist of a series of pulses, groans and moans reach 200 decibels and can be as low as 14 Hz. Their vocalizations can travel up to 1,600 kilometres, leading some to think that they may be able to communicate across oceans. Scientists speculate whales use these vocalizations not only to communicate, but also to sonar-navigate the dark depths of the ocean.

Blue whales belong to a group called baleen whales. This means they use a structure called a baleen to filter water for food. The baleen is attached to the whale’s upper jaw. It’s made up of a series of plates constructed of a material similar to fingernails. Ironically, the largest animal on earth eats tiny shrimp-like creatures called krill and uses its baleen to filter up to six to seven tonnes of food per day. Equipped with their baleen, blue whales can intake over 64,000 litres of water in a single gulp by expanding the pleated skin on their throat and belly. They then use their tongue to force the water through the baleen, where the food is trapped in the plates, and expel the water. The average feeding speed of a blue whale is two to 6.5 km per hour. They can reach speeds of 33 km per hour when travelling and can accelerate to 48 km per hour when chased or are otherwise agitated. These speeds make them one of the fastest whale species.

While they normally travel alone, blue whales have been known to travel in small groups of two or three. They alternate between swimming in shallow and deep water and can dive to great depths. Blue whales average depths of 45 to 90 metres and have been recorded as deep as 355 metres below the water surface. They are able to stay submerged for up to 50 minutes, although 15-minute intervals are more common. When they reach the surface, blue whales breathe by shooting water out of their blowholes; this is called spouting. They will do this approximately 10 times when they return to the surface, and each spout sends a column of water vapour as high as six metres into the air!  

Blue whale babies, called calves, are born six to seven metres long in the late fall and early winter. The calves nurse for seven to eight months during which time their weight increases by 90 kilograms and they grow 4.2 centimetres per day. Females have one calf every two to three years, and the gestation period is 10 to 11 months.

The blue whale, like many whale species, is listed by the Canadian government as endangered. A combination of factors has contributed to this status. These factors include, but are not limited to, entanglement in fishing equipment, poaching, interactions with ships, climate change and water pollution.

Water pollution is a major contributing factor to aquatic species at risk in Canada, and many people are unaware that the products they use contribute to the problem. Everyday chemicals, especially those used in your garden, can result in water pollution through runoff. Sewage, drain water and runoff from urban areas can travel to the ocean via ground water, streams and rivers and are amongst the highest pollutants in aquatic environments.

You can help cut down on pollution by using environmentally friendly alternatives to everyday household chemicals, and when you must use chemicals, ensure that you dispose of them properly instead of dumping them down the drain. Many stores have return programs, and every community should have specialized facilities for chemical leftovers and their containers. Some examples of chemicals that deserve special consideration are household paints and stains, engine oils, batteries and some electronics such as computer monitors and televisions.

You can also use environmentally friendly products and gardening supplies when working on your property. For example, when staining your deck, consider using an environmentally friendly stain, available at many hardware stores. 

Another way to minimize chemical use is to use compost instead of fertilizers. Not only does this provide your garden with a natural, nutrient-rich soil, but it’s free and cuts down on gardening costs. Approximately 30 per cent of household waste is made up of compostable kitchen scraps and yard waste. Once composted, the soil provides nutrients to plants and can also help protect them from garden pests. Worms and beneficial insects, such as rove beetles, provide additional nutrients to the soil, and some feed on garden pests like ants, aphids and grubs. By attracting these helpful insects, you are also cutting down on the need for pesticides and other chemical pest control substances. Using biological pest control is a safe and environmentally friendly approach to garden maintenance.  For more information about composting and green gardening practices, check our Get Gardening: Be Green and Garden Care sections.

As always, leaving a part of your property wild, especially shoreline property, benefits local wildlife of all types and is a good way to give back to the environment in your community. To find out more about how to garden to benefit wildlife, please read our article on Gardening for Wildlife.