July 18, 2018

How many species have gone extinct ? 941 species are listed in IUCN Redlist!

A. It depends on the definition of species. If you count only described (known) species, 941 species among evaluated 43700 taxa are listed as extinct or extinct in the wild in IUCN Redlist database. (see PNG for a method to get this number from IUCN's Red List website ). Note that extinct species recorded in 2002 does not mean the species went extinct in 2002 but is decided as extinct in 2002. In addition, there are many undescribed species (see Monitoring and biodiversity indices). Therefore the number of extinct species may be bigger if we include undescribed species. It is noted that the number of extinct species /day is >1, probably ca.10 or more (e.g. WWF website). However, if the extinction rate is not significantly different between described and undescribed species, this is definitely far overestimation.

June 12, 2018

Why do those who eat beef criticize whaling?

I would like to introduce the debate on whaling when I was a visiting researcher in USA in 1992.
I usually introduced an episode of "The wolf and the dog in the fables of Aesop":
A Dog offered to help a Wolf get regular feed from his Master. The Wolf saw a bald spot on Dog’s neck where the collar sat. Goodbye said Wolf. Better starve free than be a fat slave.
Eating livestock is a double sin. Those who eat beef rob the cow's freedom and kill. In my experience, nobody refuted me. But... 1 decade later, I knew that many non-Japanese students in ecology became vegetarians. I respect that they deeply seek self-consistency. But I do not agree with them if they forced others to adopt their new rules.

March 22, 2018

Age-structured models. Background readings Lawson TA & Hilborn R (1985) Equilibrium yields and yield isopleths from a general age-structured model of. - ppt download

Age-structured models. Background readings Lawson TA & Hilborn R (1985) Equilibrium yields and yield isopleths from a general age-structured model of. - ppt download

October 15, 2017

Greeting Cheers on the Society of Population Ecology

Dear Participants of the 33rd Annual Meeting of the Society of Population Ecology,
Welcome to Fukuoka,
Non-Japanese members of our society may mind the future of this society if you heard a plan to collaborate the editorial boards between Population Ecology and Ecological Research.
Do not worry! Three present and past presidents of this society were also the past president of Ecological Society of Japan. Many steering committee members of this society overlap with the national committee members of ESJ. We plan to develop our activities of Population Ecology with ESJ.
Our slogan is NOT Japanese first, but Ecology first! Please enjoy this meeting and Fukuoka!
I hope your happiness, success, and the development of ecology!

August 16, 2017

Is tuna farming so bad? It depends on the situation including mortality in the cage.
Date: Wed, 16 Aug 2017 17:00:55 +0900
1. Catch of less than 3 years old is growth overfishing.
2. Under the current fishing mortarity, % SPR was less than 10%, implying heavy overfishing.
3. Catch of less than 5 years old or catch during spawning season is probably recruitment overfishing if we seek 40% SPR as sustainability constraint, the price during spawning season is much cheaper than during the winter, and assuming M=0.25/yr. I used the method by Matsuda et al. (1999).
4. Under the optimal age- and season-specific fishing, YPR under sustainable fisheries is nearly the same as the current YPR under current overfishing. We also expect a big stock recovery under the optimal fishery.

1) We can incorporate the effect of cultivated tuna. The impact on stock depends on the age caught, but as cultured tuna grows. It will rise in price. Tuna far,omg is not bad unless the mortality rate in the cage and the cost of cultivation are not too high.
2) However, a small part of immature tunas caught in purse seine are used for tuna farming (but we do not know the published data). Perhaps 3)It also depends on the cost of feeding and mortality in the cage (unpublished). In addition, now Japanese tuna farming is probably excessive and a large part of cultured tunas is not sold on the market. This implies an economic failure of tuna farming industry.
4) But reproductive values (ecological sense) during spawning season is only ca.10% larger than that during non-spawning season. Therefore, tuna farming is reasonable unless most of cultured fish are discarded on the market, the cost of cultivation or the mortality rate in the cage is not too high, or and these data are not published.

Matsuda H, Yamauchi A, Matsumiya Y and Yamakawa T (1999) Reproductive value, harvest value, impact multiplier as indicators for maximum sustainable fisheries. Environmental Economics and Policy Studies 2:129-146.
See also my Japanese blog.

March 31, 2017

I look forward to discussion with the audience of "Mission Blue" on April 13, Kyoto University.

March 30, 2017

Toward the Establishment of Technical Standards for Use in Marine Environment Impact Assessment pdf
30th March 2017
UN Conference Room 8
(Lunch will be provided in the Vienna Cafe area starting at 1:00 p.m.)
1:15 p.m. to 2:45 p.m.
Back Ground
In 2016, the International Organization for Standardization (ISO) established a working group (TC8/SC13/WG4) to make ISO standards on Marine Environment Impact Assessment (MEIA) applicable to all maritime areas. Actually, the existing international treaties on the law of the sea incorporate ISO standards and utilize them, because ISO standards are basically based on scientific evidence and technology, and therefore comparatively easy for States to accept. Meanwhile, in January 2017, the International Seabed Authority (ISA) published the Discussion Paper on the Development of “Environmental Regulations”. In this way, currently, the rules and standards on MEIA are being developed, not only in the PrepCom for new treaty of BBNJ, but also in the multiple arena,.
Against this background, ISO, ISA and Japan Agency of Marine of Marine Earth Science and Technology (JAMSTEC)will jointly organize this side event to introduce the concept of the possible new ISO standard for MEIA, that will be compatible with future ISA regulations, showing the new technology for MEIA developed by JAMSTEC and related institutes.
Event Agenda
General Introduction:Dr. Yoshihisa Shirayama, JAMSTEC
Current Development of Technical Standards for MEIA,Dr. Makoto Seta, YNU-DEEPS
ž International Seabed Authority’s provision for EIA in the Area under approved plan of work, Dr. Sandor Mulsow, ISA,
ž Possible new ISO standards on MEIA, Prof.Koichi Yoshida, YNU-DEEPS
Open Discussion:Moderator,Prof. Koichi Yoshida
Closing remark:Prof. Yoshiyuki Nakamura, YNU