Needs for assisted migration?

Rapid climate change has already caused changes to habitat for plant and animal species, leading to local extinction of some species, if species could not recolonize to new habitat or adapt to local environment. The subject of assisted migration (or managed relocation), which intends species to transfer to the suitable habitat outside of species range, has become common for couple of years.

When I learned about the subjects of assisted migration, I could not accept it as the real matter at first. But now, I have realized that the needs for the assisted migration is became widely accepted, as the risk of species extinction has been evaluated from the myriad researches such as long-term ecosystem monitoring and climate-niche model studies. Actually, some guidelines to decide assisted migration has already been proposed.

On the other hands, some researchers have questioned whether assisted migration would be an effective strategy to conservation, because of its risks. Transferring the species to the outside of the original species range cause similar problems as invasion of exotic species to recipient habitat: extirpation of local species, introduction of new pests and herbivore, and hybrids between local and introduced species have already been reported. Consequently, they insisted that the risks of assisted migration were often uncertain, and precautionary principle which species should not be transferred to the outside of habitat should be undertaken.

Discussions on this topic has been continued on TREE. Majority of them insisted that the necessity of individual and qualitative assessment of needs, benefits and risks of assisted migration, albeit to precautionary principle. On the contrary, one mentioned that assisted migration is not a fundamental solution to prevent extinction, but a "techno-fix".

The problem underlying the transfer of species along with climate change is slightly different from other problems on conservation biology. Existing problems such as habitat degradation or invasive species probably have "ideal states", which is preservation of habitat or original state before invasive species had been introduced. However, loss of habitat due to climate change does not have such "ideal state", rather the situation is continued to be getting worse, and may not be recovered. The motivation is to make a situation to better, at most. Therefore "do-nothing policy" may not be a better solution, and precautionary principle could not be applied to this type of problem.

As the most of authors pointed out, the vulnerability of species to extinct with climate change, and the potential risks underlying assisted migration are often uncertain. Small scale experiment of assisted migration in various endangered genera or species should urgently be taken to reduce uncertainty.

Original article:http://motoshi.tk/index.php?Web%C6%FC%B5%AD%2F2009-07-13

Biodiversity conservasion and forest management

On July 7, Mainichi-shimbun reported that Forestry Agency of Japan is considering biodiversity conservation in forest managements in the next revision of Forest and Forestry Master Plan.

Needless to say, biodiversity conservation should be considered in the forest management, and it may be benefits for future generations. But, the problem is that there is no substantial guideline to evaluate and conserve biodiversity in current Japan. For this reason, the article said that the committee concluded that there is urgent need to increase the knowledge and data about forest ecosystems. I agree with it.

However, as far as reading the news release from Forestry Agency, the most important message from the committee seems not to be data. One committee mentioned that following:

It is necessary to promoting adaptive management of forest with scientific point of view when we consider about biodiversity conservation in the measures. In Japan, research (on forest ecosystem) is often insufficient, so that the amount of scientific knowledge should be considered. The measures should not be assertive, rather it should emphasize that there is urgent need for research to reduce uncertainty. (translated by M. Tomita)

生物多様性を施策に取り入れるには、科学的な視点から問題を捉え、順応的な森林管理を推進することが必要。日本においては必ずしも調査研究の蓄積や分析が十分ではなく、どの程度科学的な知見が得られているかに応じて書き方を工夫することが必要。施策についても断定的に書くのではなく、むしろ不確実性を減らすために必要な調査研究が必要であることを強調すべき。

The important point is "promoting adaptive management of forest with scientific point of view". Scientists are expected not only to increase data about forest ecosystems, but rather to evaluate individual management practices under uncertainty, to give new address to the next plans, and to integrate those knowledge to discuss about common rules for the biodiversity conservation.

On the other hands, I could not agree with some opinions from the committee. For example, some attendants pointed "further necessity of road construction" or "compensation to additional cost owing to biodiversity conservation". I think those comments were probably because they had been confused loss of biodiversity in Japanese forest with existing problems about degradation of plantations due to insufficient management.

Actually, it may be true that insufficient management is one of the cause of degradation of biodiversity. But it is obvious that intensive management of plantation, especially thinning, is not directly linked to biodiversity conservation.

Management practices, like thinning or road construction, should be conducted as a part of adaptive management. And those practice should be evaluated from the scientific point of view. I hope that it should be emphasized in the final report of the committee.

Original article:http://motoshi.tk/index.php?Web%C6%FC%B5%AD%2F2009-07-07

Blogging is easy, but is it enough?

It is easy to say about something, but who cares about it?

Latest story on Asahi-shimbun said that 26.95 million people own blog in Japan. Despite this statistics did not consider about one person own multiple blog, it is obvious that not a small number of Japanese express about them on the web.

I myself have been blogging for four years since undergrad. And now, my blog has up to 100 unique access per day, even though most of the contents are not familiar to non-ecologist. At the same time, I subscribe about 100 blogs via Google Reader.

It is to say, we are now connected on the web by blogging. Especially, blog is effective tool to openly communicate and discuss with unspecified people. Thanks to blog, we are now able to access and even join to cool discussion at anywhere, anytime.

On the other hands, blog would waste our time. I actually update my blog almost everyday, but most of the article do say just what I did today. Who cares about what I did in my study, what I ate for lunch ...etc., every day?

Blog is convinient to express ourselves, however, articles should be selected and edited for open discussion.

For this reason, I opened this blog. This blog may not publish the article on very lastest topics, rather I would pick-up and edit my essays from my original blog.