21 research outputs found
Unusually heavy catches of ribbon fish close to the shore at Visakhapatnam
Very heavy catches of ribbonfish were observed quite close to the shore at Visakhapatnam for a very short duration. Observations were made on this fishery and certain important biological aspects Ribbonfish do not generally come very close to the shore. As such they are vei7 rarely caught in the shore-seines. They are normally caught in boatseines operating 3-4 km away from the shore and in trawl nets. It is possible that the ribbon fish shoal after spawning hit the shore chasing their food consisting of Stolephorus sp, Leiognathus sp. Etc. Which might have been moving closer to the Shore to avoid the cold upwelled water
Some glimpses of the marine fisheries in Andhra pradesh
Andhra Pradesh stands 5th in the marine fish production among the maritime states of India. The advent of mechanisation of fishing craft and introduction of mechanised fishing vessels have brought significant changes in the marine fishing industry of Andhra Pradesh. As a result of this, the fisheries harbour at Visakhapatnam has become one of the key
harbours for mechanised trawl fishing and Visakhapatnam itself has emerged as one of the most important centres for exporting marine products to foreign countrie
Blue whale Balaenoptera musculus landed at Mangamaripeta, north of Visakhapatnam
A live male Blue whale Balaenoptera musculus
Linnaeus locally called "papper meenu" measuring
12.17 m in total length was entangled accidentally
on 9th May 1994 in a synthetic drift gillnet operated
by a mechanised-cum-sail craft at a depth of
50 metres off Mangamaripeta which is situated 12
km north of Visakhapatnam. The fishermen towed
the Blue whale to the Mangamaripeta marine fish
landing centre
я╗┐The resources of hilsa shad, Hilsa ilisha (Hamilton), along the northeast coast of India
я╗┐The results of 4study on the fishery, biology, exploitation and mortality of hilsa shad (Hi1.w ilishu) are
presented. The average annual landing of Hilsa ilisha for 1979 -88 was 57 10 tomes forming 0.4% of the total
landings. The major craft and gears and [he contributions of different states arepresented. Age at first maturity
was estimated as 1.98 yem. The details of spawning migrations, maturity stages and fecundity mdiscussed.
Thetotal mortality, natural mortality and fishingmortality coefficients wereob,tainedas 1.71,0.704 and 0.9444
respectively. The present yield of4 168tonnes wasthe sameas theestimated MSY indicating theoptimum level
of exploitation
Major and minor fisheries harbours of India. 8. Fisherries harbours along the coasts of North Andhra Pradesh, Orissa and West Bengal
The present account gives information about the three major and five minor fisheries harbours along the coasts of north Andhra Pradesh, Orissa and West Benga
Marine Fish Calendar. 2. Visakhapatnam
Gear wise landing details of the fish species in the important families (e.g. Clupeidae,Scombridae, Sciaenidae, etc.), groups (e.g. sardines,mackerel, croakers, etc.) in the Vishakapatnam landing centre during 1981-1986 was provided in the article
Status of exploitation of seerfishes in the Indian seas
Seerfish production from the Indian seas during the past five decades from 1950s to
1990s, showed an increasing trend. The annual catch increased from 4,505 t in
1953 to 54,8761 in 1998. The average annual catch during the five decadal periods
k-aried from 7,278 t in 1950-'59 to 41,575 t in 1990-'99 contributing 1.5% and
1.75% respectively to the total marine fish catch of India. However, the rate of
increase through the successive decades decreased indicating the attainment of op-
;imum level of production currently. During 1950-'59, the east coast contributed
more (60%) than the west coast (40%), which changed to 36:64 during 1990-'99.
iVmong the maritime states of India, Gujarat (25.88%), Maharashtra (16.09%),
familnadu (13.59%), Kerala (13.07%) and Andhra Pradesh (12.68%) were the prime
seerfish producers during 1990-'99. Gill net (64.8%) was the dominant gear, folowed
by trawl (17.4%) and hooks and line (4%) with an average catch rate of 8.1
<g/unit, 0.24 kg/hr and 3.7 kg/unit respectively during 1995-'99. Among the five
species, the fishery was sustained only by two species viz., the king seer
Scomberomorus commerson and the spotted seer S.guttatus
The Quantum Theory of MIMO Markovian Feedback with Diffusive Measurements
Feedback control engineers have been interested in MIMO (multiple-input
multiple-output) extensions of SISO (single-input single-output) results of
various kinds due to its rich mathematical structure and practical
applications. An outstanding problem in quantum feedback control is the
extension of the SISO theory of Markovian feedback by Wiseman and Milburn
[Phys. Rev. Lett. {\bf 70}, 548 (1993)] to multiple inputs and multiple
outputs. Here we generalize the SISO homodyne-mediated feedback theory to allow
for multiple inputs, multiple outputs, and \emph{arbitrary} diffusive quantum
measurements. We thus obtain a MIMO framework which resembles the SISO theory
and whose additional mathematical structure is highlighted by the extensive use
of vector-operator algebra.Comment: 17 pages, 2 figure
Stock assessment of tunas from the Indian seas
The tuna catch in India in the small scale sector fluctuated between 23 170 tonnes and 35 610 tonnes during 1984-88, the average catch for the priod being 29 146 tonnes. In 1989, 45,240 tonnes of tunas were landed by the artisanal sector