Scientific research can be invaluable for effective MPAs. It helps managers understand the ecosystems they oversee, and can observe how those ecosystems respond to management and environmental changes.

Not all research techniques are the same, obviously. For every method that is non-invasive (such as reef surveys by divers), there are techniques that impose a greater impact on the environment. Seismic testing, as described in the previous article, is one example. Trawl surveys, a traditional fisheries science technique, can be another, particularly in areas with sensitive seafloor habitats.

The challenge arises for managers: how to balance the need for science with the need for conservation in cases where there is conflict between the two? A case in eastern Canada illustrates how one management authority has attempted to strike the balance.

The Gully MPA

Trawl surveys have been a routine part of fisheries stock assessment on the east coast of Canada for four decades. The Canadian Department of Fisheries and Oceans (DFO) uses an automated system to select random points to sample on the country’s continental shelf. Some of those random points have fallen within the boundaries of a protected site: the Gully Marine Protected Area, designated in 2004 and managed by DFO to protect a large and biodiverse marine canyon.

The Gully MPA carries general prohibitions against “disturbance, damage, destruction, or removal” of organisms or habitats within the MPA. But it also allows limited fishing for some species in certain zones. In other words, the random trawl surveys would not be the only incidents of organisms being removed from the ecosystem. However, some of the trawl surveys’ random sample points happened to coincide with areas of fragile habitat – centuries-old deepwater coral. There was conflict: one arm of DFO sought to conduct its standard research on fisheries, while another arm (management of the MPA) sought to protect habitat. DFO was already sensitive to the potential for negative public relations from this. In 2002, video of a DFO trawl survey off the east coast showed the unintentional hauling of large coral pieces. The damage revealed by the video drew media attention and public criticism.

Paul Macnab, manager of the Gully MPA, describes the process that has been put in place to manage the science/conservation conflict. “When the MPA regulations were passed into law in 2004, the survey proponents were newly required to obtain Ministerial approval for the conduct of a scientific activity in the MPA,” says Macnab. “Since then, each sampling station selected for the Gully has been assessed against prior sampling records, geological seabed classifications, and ecological data (e.g., coral) where and when available. For deeper stations on glacially relic or structurally complex bottoms where it was likely there would be negative interactions with coral – namely, contact with the trawl gear leading to impacts like removal, damage, or destruction of the coral – some applications have been denied. Stations proposed for shallower depths on sandy substrate where natural variability is high (e.g., sediment moved by storms and waves), and where there may have been significant trawling effort in the past, have mostly been approved.”

Recently, DFO fisheries scientists withdrew the Gully MPA from their survey design until greater certainty on sites within the MPA could be obtained. Gully management and the scientists are in talks now about the possibility of proactively assessing and agreeing on which portions of the MPA may be sampled safely in the future, rather than relying on one-off applications that may or may not be approved on a case-by-case basis.

“The MPA management paradox”

Macnab calls the balancing of science and conservation “the MPA management paradox”. “We need to study, assess, and monitor populations, age, abundance, closure effects, diversity, and so on – but we also need to protect the same,” he says. He says non-invasive methods are great when available, but cannot tell management everything it needs to know. Optical survey technology is evolving quickly, he says, but tissue samples are still necessary for genetic studies (such as for examining source-sink dynamics), for fatty acid or stable isotope analyses (which can provide information on diet), and for contaminant monitoring.

Notably, the regulations for the Gully allow for researchers to disturb, damage, destroy, or remove organisms and habitat in the MPA if the learning will contribute to MPA understanding and management. Drawing that line can be tricky, says Macnab. “We want our science colleagues to be out there doing their part in the MPA even if it means some risk of damage and disturbance,” he says. But he also wants to see MPA-specific programming, analysis, and follow-up on the scientists’ part – not simply a pre-existing science plan designed for other purposes and applied to the MPA in a cookie-cutter way. “We want to see targeted monitoring and more site-level, hypothesis-driven science,” he says.

The website for the Gully MPA is

For more information:

Paul Macnab, Department of Fisheries and Oceans, Halifax, Nova Scotia, Canada. E-mail: