Why Does Taiwan Also Need Marine Protected Areas for Cetaceans?

This article is fully reprinted from the Kuroshio Ocean Education Foundation: "Why Does Taiwan Also Need Marine Protected Areas for Cetaceans?"

As the negative impacts of human activity on the marine environment continue to grow, the survival of ocean life has become a cause for serious concern. In recent years, issues such as declining biodiversity, widespread coral bleaching, entanglement in fishing gear, and vessel strikes on marine animals have arisen one after another — as though the ocean itself is crying out for help. So how can we slow the damage we are inflicting on the sea?

Establishing marine protected areas (MPAs) is one of the directions the international community is working toward together. Among the many marine conservation initiatives available, designating MPAs is widely regarded as one of the more effective approaches. By establishing large-scale MPAs, human interference with the marine environment can be reduced, thereby protecting the habitats of marine life and overall biodiversity.¹ This article introduces Canada's "Gully Marine Protected Area" — the word gully referring to a submarine canyon — which is home to as many as 16 different species of cetaceans. We will also explore the lessons and practices that Taiwan can draw from this example, with the hope that this case can serve as a meaningful reference for future applications by the Kuroshio Ocean Oasis Project to designate an "Important Marine Mammal Area" (IMMA).

Canada's First Marine Protected Area in the Atlantic — The Gully MPA

Between approximately 150,000 and 450,000 years ago, the movement of vast glaciers and the erosion caused by meltwater carved out a massive submarine canyon at the edge of the Scotian Shelf off Canada's east coast — the Gully. Its deepest point exceeds 2,500 m, making it the largest submarine canyon in the North Atlantic to date. The Gully region is extraordinarily rich in biodiversity: it nurtures 30 species of cold-water corals and has accumulated sighting records for 16 species of cetaceans, including the northern bottlenose whale (Hyperoodon ampullatus), blue whale (Balaenoptera musculus), and Sowerby's beaked whale (Mesoplodon bidens), among others.

Of these, the northern bottlenose whale was listed as Vulnerable by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 1997. At the time, however, the Gully area was facing oil and natural gas development activities, which subjected local cetaceans to prolonged vessel strikes and construction noise, posing a serious threat to their survival. In response, the Canadian government established the Gully Marine Protected Area in 2004 to protect the endangered northern bottlenose whale and other precious marine life in the area.

How Was the Importance of the Habitat Assessed Before the MPA Was Established?

If the goal is to protect biodiversity in a given area, protecting the entire habitat — rather than a single species — is the most direct and fundamental approach. But how do we know whether the designated area actually encompasses the habitats that cetaceans need to survive? Through at-sea visual surveys and passive acoustic monitoring,² we can gain a deeper understanding of where cetaceans appear in a given area, when they appear, and how frequently — information that helps assess the appropriate size and boundaries of a proposed MPA.

In fact, before the Gully MPA was officially established, both government agencies and researchers had already conducted preliminary assessments and studies of local cetaceans. In 1994, Fisheries and Oceans Canada established a non-legally binding whale sanctuary at the Gully — essentially a pilot zone to test its effectiveness — covering the hatched area shown in Figure 3. The agency informed vessel operators transiting the area about its ecological importance and provided guidelines teaching ship captains how to minimise threats to cetaceans when passing through the region, with the goal of reducing the risk of vessel strikes on northern bottlenose whales as much as possible. At the same time, local researchers actively studied the distribution range and population size of cetaceans in the Gully.

Using cetacean sighting data from 1988 to 1996 — including species, group size, and sighting coordinates — combined with various environmental variables such as sea surface temperature, ocean depth, and seabed gradient, researchers found a strong correlation between cetacean occurrence and depth. Cetaceans in the Gully area are predominantly found at depths of 200 to 2,000 m within the submarine canyon. Researchers therefore recommended that the government establish a core zone boundary based on the 200 m isobath, with a surrounding buffer zone, to comprehensively protect Gully's cetaceans from the impacts of oil development and shipping.

How Does the Canadian Government Manage the Gully MPA?

Following years of surveys, Canada officially enacted The Gully MPA Regulations in 2004 and published the boundaries of the Gully Marine Protected Area within those regulations. With the exception of certain activities expressly permitted under the regulations,³ it is strictly prohibited within the Gully MPA to "disturb, damage, or destroy any living marine organism or any part of its habitat, or to remove any living marine organism" — including the subsoil to a depth of 15 m below the seabed. Dumping, discarding, or discharging any substance is likewise not permitted.

In addition, the Canadian government divided the MPA into three management zones based on water depth — Zone 1, Zone 2, and Zone 3, as shown in Figure 4. Each zone has its own distinct ecological environment, and the management restrictions differ slightly between them. Within Zone 1 — the core cetacean habitat — all fishing activity is completely prohibited. In Zone 2 and Zone 3, commercial hook-and-line fishing is permitted for species including halibut, tuna, shark, and swordfish.

Once a Marine Protected Area Is Successfully Established, Is the Work Done?

Long-term data collection is needed not only before an MPA is established, but also after — ongoing monitoring is essential to evaluate its effectiveness. Canadian researchers assessed the population dynamics of northern bottlenose whales seven years after the Gully MPA was established. They estimated approximately 143 northern bottlenose whales in the Scotian Shelf waters and found that population size and sex ratio had remained stable since 1988. While there was no dramatic increase in population numbers, this stability demonstrated that the MPA had indeed allowed the whales to maintain a steady population free from the pressures of human development.

Beyond the primary target species, other cetaceans in the Gully area also showed some changes. Researchers observed that between 1988 and 2011, the sightings per unit effort (SPUE) for some cetacean species declined while others increased — trends that may be linked to shifts in environmental conditions or food resources. Notably, however, the SPUE for Sowerby's beaked whale (Mesoplodon bidens) increased substantially after the MPA was established, rising by 21% per year.⁴ In the absence of data on prey availability for deep-diving cetacean species, scientists consider the most reasonable explanation to be that the MPA reduced human disturbance: the decrease in vessel traffic and other noise has made the Gully MPA one of the preferred habitats for beaked whales, which are highly sensitive to sound. Although the establishment of the MPA has improved habitat conditions for beaked whales, long-term monitoring must continue to ensure that management remains effective and can be adjusted in a timely manner in response to environmental changes.

The Gully MPA Has Recorded 16 Species of Cetaceans — But Hualien Waters Record an Even Higher 20!

Canada's Gully MPA currently holds sighting records for 16 cetacean species. Yet according to cetacean sighting data accumulated by the Kuroshio Foundation over more than 20 years of whale-watching voyages, Hualien waters are home to as many as 20 cetacean species — an even greater level of species diversity! However, we have observed that Risso's dolphins frequently sighted off Hualien sometimes bear scars that, in addition to natural markings, appear to have been caused by human activity. In 2023, we conducted a body scar analysis of Risso's dolphins, and the results showed that 19 out of 50 individuals (38%) carried scars suspected to have been caused by human activity. With so many cetacean species inhabiting Taiwan's eastern waters, if we continue to delay providing them with a safe ocean oasis in which to grow and raise their young, we may find that future generations will no longer be able to sit at the bow of a boat, feeling the sea breeze and watching the dolphins and whales of Hualien in all their splendour.

The Gully MPA has now marked its 20th anniversary and can serve as a model for Taiwan's future efforts to establish cetacean protected areas. The Kuroshio Foundation continues to work toward this goal through the "Ocean Oasis: East Coast Cetacean Conservation Project," which aims to have Taiwan's eastern waters recognised internationally as an Important Marine Mammal Area — providing a more complete body of background data to support future policy discussions with relevant government agencies.

¹ Biodiversity is composed of genetic, species, and ecosystem diversity — much like a stable and intricately balanced pyramid.
² Passive acoustic monitoring is a technique that uses recording devices to capture sounds produced naturally in the environment.
³ Activities expressly permitted under the regulations include:
　　● Commercial hook-and-line fishing for halibut, tuna, shark, and swordfish in Zone 2 and Zone 3.
　　● Vessel transit (subject to compliance with Canada's Shipping Act).
　　● Search and rescue, environmental emergency response, and cleanup operations.
　　● Activities related to national security, sovereignty, and public safety.
⁴ Sightings per unit effort (SPUE) = number of sighting groups / survey effort.

References

1. 【Expert Testimony】Professor Shao Guangzhao — Why Establish Marine Protected Areas?
2. World Wildlife Fund — The Gully marine protected area
3. Department of Fisheries and Oceans Canada — The Gully marine protected area
4. Lesson from Atlantic Canada's oldest marine protected area, https://wwf.ca/stories/lessons-atlantic-canadas-oldest-marine-protected-area/
5. Cetacean Biodiversity in Hualien Waters
6. Uncovering the Secrets Behind Cetacean Scars — A Body Scar Analysis of Risso's Dolphins
7. Brien, K. O., & Whitehead, H. (2013). Population analysis of Endangered northern bottlenose whales on the Scotian Shelf seven years after the establishment of a Marine Protected Area. Endangered Species Research, 21(3), 273–284.
8. Hooker, S. K., Whitehead, H., & Gowans, S. (1999). Marine protected area design and the spatial and temporal distribution of cetaceans in a submarine canyon. Conservation Biology, 13(3), 592–602.
9. Moors-Murphy, H. B. (2014). Submarine canyons as important habitat for cetaceans, with special reference to the Gully: a review. Deep Sea Research Part II: Topical Studies in Oceanography, 104, 6–19.
10. Whitehead, H. (2013). Trends in cetacean abundance in the Gully submarine canyon, 1988–2011, highlight a 21% per year increase in Sowerby's beaked whales (Mesoplodon bidens). Canadian Journal of Zoology, 91(3), 141–148.
11. Original article: Why Does Taiwan Also Need Marine Protected Areas for Cetaceans?

Further Reading