Management Approach 2: Legislation

ORDER!!! *Bangs gavel* . Today I've taken a seat at the front of my imaginary courtroom, ready to pass judgement on the effectiveness of invasive species legislation. Hope there aren't any objections to this. If there are... talk to my lawyer...

According to De Poorter (2009) legal arrangements are crucial to support and underpin practical management, particularly in protected areas. For example, Sivakumar (2003) documents the example of the Andaman Islands (see location below)  which have been experiencing biodiversity reductions from invasive species, including elephant and chital.

Location of the Andaman Islands, part of India's territory... over 1000km from the Indian mainland.

However, these invaders cannot be removed as they are native on the Indian mainland and covered by the Indian Wildlife Protection Act. Clearly painting the Andaman Islands with the same legislative brush as the Indian mainland is not good practice... I mean look far apart they are! This shows a key drawback of national legislation, a species can cause problems in one part of a country but be ok in others.

Moving from the national to the international, there are now over 50 internationally agreed legal instruments to deal with some aspect of invasive species (De Poorter, 2009). An interesting international agreement to observe is the International Convention for the Control and Management of Ships’ Ballast Water and Sediments, or, thankfully, BWMC for short. This was adopted in 2004 with the aim of controlling, the threat of invaders from ballast water. 

I think I mentioned this briefly in an earlier piece, but here’s a few fun facts to give an idea of why this is important to manage:

1. Everyday about 3000 species are transported around in ship’s ballast water or on their hulls.
2. Increasing volumes of trade, travel and tourism have led to more species than ever before being transported around the world (Carlton, 1999).
3. Introduction of invasive marine species by ships is one of the four most significant threats to the world’s oceans.

Marine invasive species presence is closely linked to shipping routes.

With a sea area of 3,000,000km², rich marine biodiversity and increasing international trade, China faces particular concerns over marine invaders (Liu, 2013). The Marine Safety Administration (MSA) is responsible for ballast water management and they don't inspect for invasive species. 

Wait, what? What about the BWMC that was adopted in 2004? Surely they HAVE to inspect for them?

Well, China has not actually adopted the BWMC regulations. In fact, nobody has actually implemented them yet. The MSA has no legal obligation to inspect ballast water as BWMC has not yet entered into force. Yes, despite the BWCM being adopted in 2004, it does not come into effect until 2016.

See the thing is, it was all well and good coming up with these regulations in 2004, but to actually come into force it required ratification by 30 states, representing 35% of world merchant shipping tonnage (De Poorter, 2009).

When it does come into force requirements will include conducting ballast water exchange at least 200 nautical miles from the nearest land and in water at least 200m in depth. Ships will also need to have a ballast water record book and implement specific management plans.

The mechanism by which ships can transport invasive species via their ballast water.

But I mean, 12 years is a loooonnnng time from adoption to implementation. It seems there are several reasons why international legislation is often slow to come into force. Negotiations can be lengthy as countries have different management capacities and priorities. This often also means legislation lacks strict rules, instead using words such as ‘as possible’, which is far from ideal.

However, it appears that it's not all doom and gloom with regards to legislation.  In the north-east U.S.A the presence of proactive legislative policies have reduced the likelihood of invasions by Orconectes rusticus (the rusty crayfish), IF regulations prohibited the transport of ALL live crayfish species between water bodies (Dresser and Swanson, 2013). Regulations that did not explicitly prohibit transport or prohibited only rusty crayfish were not effective. This suggests that the most effective form of legislation is one which does not require individuals to identify species.

Distribution of the rusty crayfish in the U.S.A., highlighting where it is considered native and invasive.

Additionally, regulations haven't been able to prevent dispersal based invasions across state boundaries through shared stream connections. Essentially, we can legislate against their anthropogenic spread, but it's hard to get nature to pick up a pen and sign on the dotted line. 

So now that substantial evidence has been presented what's my verdict on legislation? It seems that the approach can often be guilty of general ineffectiveness. In many cases this is because it doesn't actually become implemented, or when it does, it fails to take account of economic and ecological complexity, especially when tackling international issues. Overall, the jury's out on legislation as an effective management tool.

Over and out

The Invader Inspector