Tag Archives: Dynamic Ocean Management

The ocean and its inhabitants aren’t static, so why do we manage them as if they are?

Ocean wildlife spotting tours don’t necessarily run year-round, instead only going out on the water when the primary species of interest is likely to be in the area.  You may go out and see so much wildlife you can barely count, or you may go out and return without seeing anything.  If you are a fisher, you may have a number of different spots you fish from, or you may use a ‘fish finder’ that points you to where they are most likely to be.  If you could see the smaller critters – the zooplankton, the larval stages of larger marine species (including some that eventually become largely sedentary), you would see that they too move.  In the ocean, creatures move.  Some move short distances, some may cross the global ocean.  The ocean itself is highly dynamic – not just over space, but over time.  This variability in turn gives rise to variability in primary production – and this means that the preferred habitat and vital food resources also shift in time and space, giving rise to a patchy distribution of mobile species, like pelagic fishes, zooplankton, and sea turtles.

So, we have an ocean that is dynamic in both time and space.  We have species that are dynamic in abundance and distribution across time and space.  And we have people, using the ocean differently across time and space.  Yet we draw lines in the ocean, managing our use of it as if everything fitted into nice neat little boxes.  People like lines.  Lines denote boundaries, allowing us to categorise and compartmentalise the natural world neatly.  We have our Exclusive Economic Zones (EEZs) denoting countries territories.  We have marine protected areas that can look after key habitats.  But when dealing with the ocean we can see that the world doesn’t necessarily fit into such neat little boxes.  Management placed in a fixed area can work really well for some things but when dealing with mobile species – and indeed mobile people, we need something else to enhance static spatial management measures.  As outlined in a paper lead by Rebecca Lewison of San Diego State University, a team of researchers from around the globe (including myself) dynamic ocean management could be just what we need.

Continue reading The ocean and its inhabitants aren’t static, so why do we manage them as if they are?

The ocean moves – and so should marine conservation management

A casual glance at the ocean and you may just see a mass of blue.  But take a closer look.  There are waves, different colours, and different levels of water clarity.  If you could peel back the layer of water, you would see environments that are not entirely alien – like mountains, canyons, forests, grass meadows, sand, mud, and volcanoes.  The ocean is a mosaic of the most wondrous and splendid habitats, hosting a magnificent array of life.  Whilst the terrain itself may remain fairly stable, the ocean itself moves.  It’s not just the waves you can see breaking on the beach, nor the movement of the tides, or even those rip currents you really don’t want to find yourself stuck in.  Beneath the surface, you will also find movement like currents flowing at different depths, upwellings that bring cold, nutrient rich waters to the surface, and internal waves as tall as 244 meters.  Sometimes you get two water masses moving either towards or way from each other, creating oceanic fronts.

Broadly speaking there are two types of oceanic fronts.  Convergent fronts occur when the masses move towards each other.  Here the water tends to be warmer than the surrounding area, and accumulate all sorts of marine critters, algae, and even litter.  In divergent fronts, where the water masses are moving away from each other, upwellings are created bringing up nutrients from the deep.  These nutrients support phytoplankton growth, which in turn supports zooplankton, which in turn supports other marine life – including species under threat, and species we like to eat.  The thing about fronts (as with many oceanographic features) is that they are not necessarily permanent features that remain in the same place.  The ocean is dynamic and as a result the habitat for many critters that live in the water column is also dynamic.

Continue reading The ocean moves – and so should marine conservation management