Ocean Idioms

A drop in the ocean

This idiom describes something so small it seems insignificant, but that cannot be said for pollutants in the ocean, which can have far-reaching consequences for marine biodiversity.

Many pollutants entering marine environments do not break down easily and can persist for years or even decades. These so-called “forever chemicals” tend to be widely used in everyday products such as food packaging, non-stick cookware, firefighting foam, and clothing. “Many pollutants are harmful even at low concentrations,” explains Dr. Juan José Alava, Honorary Research Associate at the Institute for the Oceans and Fisheries and founder of the Ocean Pollution Research Unit.

Forever chemicals can accumulate in the marine food web, impacting top predators such as the endangered southern resident and threatened Bigg’s (transient) killer whales along the BC coast. These pollutants can even transfer from mothers to calves before birth. Bioaccumulation poses health risks not only to wildlife but also to Indigenous people who strongly rely on traditional seafood.

The problem is compounded by the myth that dilution — simply dispersing or dissolving pollutants— is enough to solve it. “Dilution is not the solution to pollution,” cautions Alava. While a pollutant might seem like just a drop in the ocean, its impacts can be anything but small. “There is a need for preventive pollution measures and proper treatment before pollutants reach our oceans,” says Alava.

Having a whale of a time

This idiom means to enjoy oneself—but not all killer whale populations will be having a whale of a time as they navigate seasonal changes across their range.

In British Columbia, two populations of resident killer whales feed on their favourite meal: Chinook salmon. While northern resident killer whales have been steadily increasing in numbers over the past few decades, southern residents have not.

Dr. Andrew Trites, Professor at the Institute for the Oceans and Fisheries, offers insight into why the populations are faring so differently. “Both populations have access to different Chinook runs in different places at different times of the year.” Unlike northern residents, who live in waters between southern British Columbia to southern Alaska, southern residents feed in waters as far south as California.

While southern residents were found to have greater access to Chinook in summer than their northern counterparts, their numbers remain low in comparison. Chinook have declined throughout the Pacific, which appears to be affecting southern residents more severely. “Any food shortages that might explain the low numbers of southern residents appears to be happening in winter and spring, when they are farther south of British Columbia,” says Trites. Understanding the threats that limit this population in each season across their range is essential to preventing their extinction.

Life comes in waves

This idiom refers to the up-and-down nature of life. In the context of coastal ecosystems, this ebb and flow isn’t just metaphorical — it’s literal.

“Life in the ocean is cyclical,” explains Dr. Anna McLaskey, Research Associate at the Institute for the Oceans and Fisheries. “Activities and populations vary over the course of a day, across seasons, and over years.” Strong changes in sunlight, temperature, and winds drive these seasonal waves of life in British Columbia’s waters.

Phytoplankton — the microscopic plants that form the base of the marine food web — “grow exponentially during the first extended period of calm, sunny days in spring,” says McLaskey. This spring bloom feeds a surge in zooplankton, whose growing populations graze down the initial wave of phytoplankton. But this isn’t the end of the cycle — instead, it “allows a more diverse community of smaller phytoplankton to take its place.”

As the seasons shift, so do the diets and feeding strategies of zooplankton. During the winter months, “life may slow down, but it doesn’t stop. Carnivores are active and many omnivores switch to other foods like nanoflagellates — tiny organisms that eat bacteria,” McLaskey explains. Seasonal ‘waves’ in phytoplankton and zooplankton communities ultimately determine the quantity and quality of food available to consumers at higher trophic levels, such as fish and marine mammals.

Smoke on the water

This idiom warns: trouble is brewing. As climate change alters wildfire regimes, that warning is extended to aquatic ecosystems.

Wildfires play an important role in moving materials from the land to freshwater and marine environments, supporting nutrient cycling and aquatic food webs. However, “as fire seasons become longer and more intense in British Columbia, we may see increasing and prolonged inputs of fire-derived materials to both freshwater and coastal ecosystems, with consequences for water quality, carbon cycling, and marine food webs,” explains Emily Brown, who undertook this work as a part of her MSc at the Institute for the Oceans and Fisheries (IOF).

In the Fraser River Basin, up to 16.3% of changes in water quality could be linked to wildfire activity. “This demonstrates that fire plays such a significant role in water quality in this region and should encourage managers to monitor water quality more closely after wildfires,” said Brian Hunt, Associate Professor at the IOF. Understanding how wildfires affect aquatic systems is crucial to protecting them from even more ‘smoke on the water’ under future climate change.

Taking a nosedive

This idiom is often used to describe something suddenly descending—like a malfunctioning airplane. But for pinnipeds such as seals and sea lions, a nosedive is just another day in the ocean.

Pinnipeds are uniquely adapted to dive and stay underwater on a single breath for extended periods. As part of her PhD research at the Institute for the Oceans and Fisheries and UBC Department of Zoology, Dr. Rhea Storlund studied what makes this possible.

“Routine dive behaviour in pinnipeds is tied to their anatomy,” she explained. Contrary to the idiom’s suggestion, the key structure isn’t the nose—it’s the aortic bulb, a portion of the heart that is relatively enlarged in pinnipeds. “Individuals with larger aortic bulbs can spend more time foraging during typical dives.”

As climate change alters marine communities and human disturbances like vessel traffic increase, pinnipeds may be required to dive for longer durations. Despite their remarkable adaptations, “animals with smaller aortic bulbs may be less able to adjust their diving to reach deeper or more dispersed prey, potentially making them more vulnerable to environmental change,” Storlund says.

Stuffed to the gills

This idiom refers to someone who has eaten far too much — though it doesn’t hold up under biological scrutiny when it comes to fish.

“Gills on a fish line up anatomically to where the neck is on a human,” explains Dr. Daniel Pauly, University Killam Professor at the Institute for the Oceans and Fisheries. “When someone says they’re full ‘to the gills,’ it’s like saying they’re stuffed all the way up to their neck.”

Although unrelated to food consumption in fish, gills play a vital role in supplying the oxygen fish need to grow. According to Pauly’s Gill-Oxygen Limitation Theory, gills, which are two-dimensional surfaces, can’t keep up with the oxygen demands of a fish’s growing three-dimensional body. As a result, “fish growth is constrained by the surface area of their gills,” Pauly explains.

As climate change warms the oceans, less oxygen is available for fish to invest in growth, causing them to stop growing at smaller sizes. Additionally, some fish will no longer be able to ‘stuff themselves to the gills’ with food as the waters become too warm in lower latitude regions — prompting many species to shift their ranges toward the poles.

Once in a blue moon

This idiom refers to something rare, and the word choice is especially fitting given the somewhat infrequent yet predictable tidal patterns influenced by the moon.

“The lowest lows and the highest highs occur around the new moon and full moon,” explains Dr. Chris Harley, Professor at the Institute for the Oceans and Fisheries and Department of Zoology. As a result, there are extreme tides about every 2 weeks, and exceptionally low tides when new or full moons aligns with solstices.

Variability in the timing of low tides influences the thermal stress experienced by intertidal plants and animals. In the Salish Sea, extreme low tides often occur around midday during summer. As temperatures continue to rise with climate change, extreme low tides may push some species beyond their thermal limits, increasing the risk of localized extinctions. The 2021 heatwave saw widespread die-offs of intertidal life and was especially severe because it coincided with extremely low tides.

Also, rarer lunar cycles are worthy of this idiom. “There is an 18.6-year cycle in the moon’s orbit, with the lowest summer low tides occurring every 18-19 years,” says Harley. “So, we’ll have some extreme lows this summer.”

Ships passing in the night

This idiom refers to fleeting or unnoticed encounters. In the world of illegal fishing, however, it takes on a much more literal and troubling meaning.

While fishing on the High Seas remains essentially unregulated, coastal nations have exclusive economic zones — extending 200 nautical miles from their shorelines — where only they have the right to catch marine resources. Unfortunately, monitoring these zones is challenging in many countries, especially, many in the Global South, contributing to the growing problem of illegal fishing.

“Illegal fishing vessels often take advantage of the cover of night, switching off their lights to avoid detection,” explains Dr. Rashid Sumaila, University Killam Professor at the Institute for the Oceans and Fisheries and the School of Public Policy and Global Affairs (SPPGA). Small vessels often literally pass by larger vessels to collect the illegally caught fish and transport it to shore for sale.

Organizations like Global Fishing Watch are using satellite technology to bring greater transparency to human activity at sea. But technology alone isn’t enough. “Legal systems must work hand-in-hand with environmental monitoring efforts to strengthen surveillance,” Sumaila says.