Category: New Research

Climate change has impacted global fisheries for decades

CheungGraphic_web_editedA new paper from the Sea Around Us Project published in the journal Nature reveals that warmer ocean temperatures are driving marine species towards cooler, deeper waters, and this in turn, has affected global fisheries catches.

William Cheung, Reg Watson and Daniel Pauly used temperature preferences of fish and other marine species as a sort of “thermometer” to assess effects of climate change on the world’s oceans between 1970 and 2006. They found that global fisheries catches were increasingly dominated by warm-water species.

Click on the image to see how the catch composition of global fisheries has changed in different parts of the world.

To find out more about the research you can access the following resources:
Comment piece in Nature News & Views
Press release
Article published in Nature

Chinese foreign fisheries catch 12 times more than reported

China DWF mapChinese fishing boats catch about US$11.5 billion worth of fish from beyond their country’s own waters each year – and most of it goes unreported – this is according to a new paper led by the Sea Around Us Project, published in the journal Fish and Fisheries.

The study estimates that China’s catch in foreign waters is about 12 times greater than what the country reports to the United Nation’s Food and Agriculture Organization, an international agency that keeps track of global fisheries catches.

Much of the fishing occurs off the coast of West Africa.

You can read more about the findings at Nature, “Detective work uncovers under-reported overfishing.”

See the scientific article, published in Fish and Fisheries, here (open access).

And get the press release and associated materials, including a map illustrating where and how much Chinese vessels currently fish beyond their own waters.

Jellyfish in the Mediterranean

Jellyfish (Cotylorhiza tuberculata) with juvenile fish near Hvar Island, Croatia. (Photo © Tihomir Makovec)

A new journal article from the Sea Around Us Project reviews knowledge of jellyfish in the Mediterranean Sea, including how the abundance of a number of native and invasive species has changed over time, and what could be causing the changes. In addition, the authors offer advice on how to manage jellyfish blooms – a challenge given the high levels of uncertainty and variability.

Lucas Brotz, a PhD student supervised by Dr Daniel Pauly, is the lead author on the paper, which is published in Acta Adriatica.

You can access the paper here.

Brotz L and Pauly D (2012) Jellyfish populations in the Mediterranean Sea. Acta Adriatica 53(2): 211-230.

New database of marine aquaculture launched

The new Global Mariculture Database (GMD), released by the Sea Around Us Project, offers detailed information on the where and what of mariculture around the world since 1950. By mapping the production of marine aquaculture at smaller scales than the usual national scale and by digging deeper into the species being farmed, the GMD provides room for new insights into marine aquaculture.  And all of this information is now available online for anyone to browse on the Sea Around Us Project website!

The GMD confirms reports by the Food and Agriculture Organization of the UN (FAO) that the amount of seafood produced by marine aquaculture has tripled since 1950 – a massive increase. During this time, there has also been a shift in the type of seafood produced globally, with a larger percentage of predatory species, such as salmon and tuna, farmed around the world today compared to 1950. In the past, the relative production of species lower on the food chain, like mussels and oysters, was higher. This phenomenon has been described as “farming up the food web” a term derived from the concept of fishing down marine food webs.

In keeping with the Sea Around Us Project’s goal of improving public access to global fisheries and aquaculture information, this Global Mariculture Database (GMD) is freely available online at www.seaaroundus.org.

To find out more about the GMD and how it was created, you can read the paper recently published in the journal Marine Policy:

Campbell B and Pauly D (2012) Mariculture: a global analysis of production trends since 1950. Marine Policy 39: 94-100.