2013 has been a big year for seafood issues. Late last year, an Oceana investigation put mislabeling on a lot of radars, legislative ears in Washington perked up. Then, as recently as this week, Target joined a list of retailers opposing genetically modified salmon sales. Quality and sustainability for seafood remain hot issues for everyone involved, including companies as big as McDonald's.

Now, Greenpeace has released its latest "Carting Away the Oceans" (CATO) report, which gives scores to seafood retailers based on factors such as sourcing policies, political initiative participation and types of products stocked.

In this year's rankings on the CATO list, Whole Foods reclaimed the top slot, which it previously held in 2008. Greenpeace credits Trader Joe's as well, for having improved its practices—and even Walmart earned some praise for improvement, even though the retail giant failed to crack the top 10.

According to Greenpeace's scoring system. These are the top 10 retailers in the sustainable fish world right now:

1. Whole Foods (7.3)
2. Safeway (7.1)
3. Trader Joe's (7.0)
4. Wegmans (6.9)
5. Harris Teeter (6.7)
6. Target (6.4)
7. Aldi (6.3)
8. Ahold (6.1)
9. Delhaize (5.7)
10. Price Chopper (5.6)

Here are the extended rankings, which you can read more about in the full report.

(Image credit: Greenpeace)

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