scholarly journals Characterisation of artisanal catches in selected fishing areas of the Lower Tana Delta and Malindi-Ungwana Bay, Kenya

2020 ◽  
Vol 19 (1) ◽  
pp. 45-53
Author(s):  
Mumini Dzoga ◽  
Danny Simatele ◽  
Cosmas Munga
Keyword(s):  
Clarias Gariepinus ◽  
Abundant Species ◽  
Fishing Effort ◽  
North Coast ◽  
Marine Habitat ◽  
North East ◽  
Fisheries Resources ◽  
The North ◽  
Scomberomorus Commerson ◽  
Catch Composition

Shore-based assessment of fisheries resources in Ngomeni, Kipini and Ozi fishing areas of Malindi-Ungwana Bay and the Lower Tana Delta on the north coast of Kenya was conducted from January to December 2017 to establish catch composition, species richness, and fishing effort (catch-rate, number and types of fishing gears and crafts) in the marine, estuarine and riverine habitats. Distinct catch composition (R = 0.27, P < 0.05) was observed across the three habitats. Catch composition differed significantly spatially and seasonally across the three fishing areas, and between the north east (NE) and south east (SE) monsoon seasons (R = 0.332, P < 0.05). The wolf herring, Chirocentrus dorab, was the most abundant fish species in Ngomeni, centrally located in Malindi-Ungwana Bay, while the catfishes, Arius africanus and Clarias gariepinus, were the most abundant species in Kipini and Ozi, respectively. Gillnets operated from dhows (mashua) and fibre-reinforced plastic (FRP) boats in Ngomeni (marine), and canoes using-basket traps in Ozi (riverine), landed significantly larger Spanish mackerel, Scomberomorus commerson, and sea catfish, Arius africanus (Kruskal Wallis test: Df = 2; F = 197.141; p < 0.001; Df = 2, F = 490, p < 0.001), respectively. Species diversity by area in combination with habitat and type of fishing craft showed higher diversity for Ngomeni in the marine habitat with mashua fishing crafts than in Kipini. Significantly different catch rates (Df = 2, F = 10.43, p<0.001; Df = 1, F = 5.897, p < 0.021) were observed in the three (3) fishing areas and during the NE monsoon and the SE monsoon, respectively. Canoes were the most common fishing craft used, especially in Ngomeni, accounting for 37.1%, and 97.5% in Ozi, while mashua crafts accounted for 44.5% of the total fishing craft in Kipini. Monofilament nets were most common in Ngomeni (34.0%) while basket traps dominated the Ozi site at 63.6%. The Kipini area was dominated by handlines (28.8%). It is therefore evident that the three (3) fishing areas of the Malindi-Ungwana Bay and Lower Tana Delta showed significant differences in catch composition and size of fish caught, attributed partly to the variation in habitat types and fishing methods between the sites. Overall, the Ngomeni area was characterized by more advanced fishing craft with the majority powered by engines, including mashua and FRP boats, compared to Kipini and Ozi fishing areas where canoes were dominant.

scholarly journals Species composition and diversity of cast net fisheries in New Calabar River, Niger Delta, Nigeria

2018 ◽  
Vol 4 (1) ◽  
pp. 19-26 ◽  
Author(s):  
HE Dienye ◽  
OA Olopade ◽  
SA Toby
Keyword(s):  
Decapod Crustacean ◽  
Abundant Species ◽  
Diversity Indices ◽  
Fish Stock ◽  
Base Line ◽  
Fisheries Resources ◽  
Fish Samples ◽  
Catch Composition ◽  
Rivers State ◽  
Management And Conservation

A study on the catch composition and diversity of cast net fisheries was conducted between May and August, 2017 in the New Calabar River, Rivers state, using cast net of varying mesh sizes (1.5mm and 2.5mm). Fish samples were collected from three sampling stations, viz. Station1- Aluu, Station 2- Choba and Station 3- Iwofe. The fish species recorded comprised of 26 species under 11 families, and one decapod crustacean. The three most abundant species were; Coptodon guineensis (25.11%), Coptodon zilli (18.56%) both from the Cichlidae family, and Penaeus nitialis (10.90%) from the Penaeidae family, while the least abundant species was Liza grandisquamis (0.13%) from the Mugilidae family. The diversity indices showed that station 2 recorded the highest number of species (21) while station 1 recorded the lowest with (12) species. Simpson’s indexes of diversity, Simpson’s reciprocal index, Shannon- weiner index, and Pielou’s evenness index, were estimated. This study serves as a base line data which will assist relevant bodies in the management and conservation of fisheries resources in the New Calabar River. It is therefore recommended that for an improved and sustainable exploitation and management of fisheries resources of the New Calabar River, proper monitoring and management for fish stock must be done.J. Biodivers. Conserv. Bioresour. Manag. 2018, 4(1): 19-26

A Note on the Diet Synaphobranchus Kaupi (Pisces: Synaphobranchidae) from the Porcupine Seabight, North-East Atlantic

1998 ◽  
Vol 78 (4) ◽  
pp. 1385-1388 ◽  
Author(s):  
Afonso Marques
Keyword(s):  
Atlantic Coast ◽  
Abundant Species ◽  
West African ◽  
East Atlantic ◽  
Porcupine Seabight ◽  
Middle Atlantic ◽  
North East ◽  
The North ◽  
Fourth Level ◽  
The Usa

The diet of Synaphobranchus kaupi from the Porcupine Seabight is described. A sample of 110 eel stomachs containing food, were analysed and the general size–depth trend among eels with food in their stomachs. Larger individuals are found in deeper waters. Fish are the main prey for larger eels and crustaceans are preferred by smaller individuals.Synaphobranchus kaupi Johnson, 1862 is a slope dwelling eel, abundant in the north-east Atlantic Ocean from 230 to 2420 m deep on the continental slope (Haedrich & Merrett, 1988). It is the most abundant species on the slopes of the Porcupine Seabight, off south-west Ireland (Merrett et al, 1991; Priede et al., 1994) and was classified as a benthopelagic predator of the fourth level, predator of predators (Saldanha, 1991).The diet of S. kaupi has been described from the slope off the middle Atlantic coast of the USA (Sedberry & Musick, 1978), from the Portuguese slope and in the Bay of Biscay (Saldanha, 1991), from the west African slope (Merrett & Marshall, 1981; Merrett & Domanski, 1985) and from the Rockall Trough (Gordon & Mauchline, 1996).Our specimens were captured during a joint IOS/SAMS survey (Merret et al., 1991). From a total catch of 8792 S. kaupi, captured between 1979 and 1983 in the Porcupine Seabight, ranging from 470 to 2230 m deep, fish stomachs were removed aboard ship and 110 with food were kept in 5% formalin for further analysis.

Faecal DNA detection of invasive species: the case of feral foxes in Tasmania

2007 ◽  
Vol 34 (1) ◽  
pp. 1 ◽  
Author(s):  
Oliver Berry ◽  
Stephen D. Sarre ◽  
Lachlan Farrington ◽  
Nicola Aitken
Keyword(s):  
Invasive Species ◽  
Species Identification ◽  
Dna Analysis ◽  
North Coast ◽  
Distribution Data ◽  
Faecal Dna ◽  
Non Invasive ◽  
North East ◽  
The North ◽  
Pcr Multiplex

Early detection of biological invasions is critical to reducing their impact, but because invading organisms are initially at low densities, detection and eradication can be challenging. Here, we demonstrate the utility of faecal DNA analysis for the detection of an elusive invasive species – the red fox, Vulpes vulpes, which was illegally introduced to the island of Tasmania in the late 1990s. Foxes are a devastating pest to both wildlife and agriculture on the Australian mainland, and would have a similarly serious impact in Tasmania if they became established. Attempts to eradicate foxes from Tasmania have been hampered by unreliable distribution data derived mostly from public sightings. In response, we developed a highly accurate and reliable DNA-based PCR-multiplex test that identifies foxes from field-collected faeces. We also developed a sexing test, but it was reliable only for faeces less than three weeks old. Faeces are a useful target for DNA-based diagnostics in foxes because they are deposited in prominent locations and are long-lasting. The species identification test formed a key component of a Tasmania-wide detection and eradication program. In all, 1160 geo-referenced carnivore scats were analysed; of these, 78% contained DNA of sufficient quality for species identification. A single scat from the north-east of the island was identified as belonging to fox, as was a nine-week-old roadkill carcass from the north coast, and a blood sample from near Hobart, triggering increased control and surveillance in these regions. The accuracy, reliability, and cost-effectiveness of non-invasive tests make them a critical adjunct to traditional tools for monitoring cryptic invasive species that are at low density in the early stages of invasion and when eradication is still an option.

Redescription and new records ofCeltodoryx ciocalyptoides(Demospongiae: Poecilosclerida)—a sponge invader in the north east Atlantic Ocean of Asian origin?

2011 ◽  
Vol 91 (2) ◽  
pp. 347-355 ◽  
Author(s):  
Daniela Henkel ◽  
Dorte Janussen
Keyword(s):  
Abundant Species ◽  
East Atlantic ◽  
West Pacific ◽  
North West ◽  
North East ◽  
The North ◽  
First Case ◽  
The Pacific ◽  
Inshore Waters ◽  
Taxonomic Studies

In 1996 a sponge was found in a well studied area in the Ria of Etel, Brittany, France, that had never been recorded there before. This sponge was later described as a new species and genus,Celtodoryx girardaeby Perezet al.(2006), who concluded that it is probably an invasive species. Over several yearsC. girardaewas found to occur successively in the Gulf of Morbihan, France, and Oosterschelde estuary, Netherlands. This sponge is characterized by an extensive spatial broading and therewith it rates today among the dominant benthic megafauna in the shallow waters of the Gulf of Morbihan and Dutch inshore waters. During our recent survey of the Chinese Yellow Sea sponge fauna, we found an abundant species with close morphological similarities toC. girardae. Further taxonomic studies have revealed that both the Chinese and European sponges are in fact conspecific withCornulum ciocalyptoidesdescribed by Burton (1935) from Posiet Bay, Sea of Japan and later recorded from other localities of the North West Pacific (e.g. Koltun, 1971; Sim & Byeon, 1989). In this paper we transfer the species of Burton fromCornulumtoCeltodoryxand consequently it becomes the senior synonym ofC. girardae. Furthermore, we conclude thatCeltodoryx ciocalyptoideswas introduced to the North East Atlantic from the North West Pacific with aquaculture of the Pacific oysterCrassostrea gigasas the probable vector. This is probably the first case recorded so far of a sponge species being transferred from one ocean to another by human activity.

The marine algae of the Solomon Islands and their place in biotic reefs

1969 ◽  
Vol 255 (800) ◽  
pp. 433-442 ◽  
Keyword(s):  
Marine Algae ◽  
Solomon Islands ◽  
North Coast ◽  
General Situation ◽  
Algal Flora ◽  
Tropical Regions ◽  
North West ◽  
North East ◽  
The North ◽  
Marine Algal

The Royal Society Expedition to the Solomon Islands aimed at examining the biogeographical relationships between these islands and other island systems of the western tropical Pacific. The marine party also studied intertidal and reef ecology. Comprehensive collections of benthic marine algae were made at the main localities visited (Florida Islands, north-west and south-east Guadalcanal, Matiu Island off the north coast and Batuona and Ulukoro Islands off the south coast of New Georgia, Banika Island in the Russell Islands, and south-east Gizo Island). Additional small collections were obtained from Kolombangara and the north coast of San Cristobal. Habitat notes accompanied each collection and preliminary determinations were made in the field where possible. General ecological observations on the reefs included profiles selected after a preliminary survey of an area. Such profiles (see below) indicate the general situation but are not based on detailed transect work; restricted time and the great variation in distribution of organisms over the reef surface (especially in the moat) rendered isolated detailed transects of limited value. The marine algal flora of the Solomon Islands has been one of the least known in tropical regions. Setchell (1935) recorded nine species from Malaita Island and also several taxa from Sikaiana Island (in the Stewart Islands, north-east of Malaita Island) and from Bellona Island, south of the Solomon Islands. Levring (i960) recorded a number of species from Rennell Island, near Bellona Island. Otherwise there are only a few scattered records in taxonomic monographs.

Management and Developement of Fisheries in the North Atlantic

1973 ◽  
Vol 30 (12) ◽  
pp. 2402-2418 ◽  
Author(s):  
G. Möcklinghoff
Keyword(s):  
Fish Species ◽  
North Atlantic ◽  
Mesh Size ◽  
Fishing Effort ◽  
Conceptual Basis ◽  
East Atlantic ◽  
International Council ◽  
North East ◽  
The North ◽  
The North Atlantic

The "conventional" fish species of the North Atlantic are mostly being fully utilized or nearly so, some having been overexploited in recent years. Recommendations for management are made by the International Commission for the Northwest Atlantic Fisheries (ICNAF) and the North East Atlantic Fisheries Commission (NEAFC). The factual and conceptual basis for management is provided by the scientists of many nations, coordinated by ICNAF and by the International Council for the Exploration of the Sea (ICES). The need in nearly every major North Atlantic fishery is to limit fishing effort, which in practical terms means allocating quotas to states. Such action has been initiated by ICNAF and is under active consideration by NEAFC. The process would have been easier if it had been begun a few years earlier, before several major stocks became depressed, but since new ground is being broken internationally the delay was almost inevitable. Regulations of mesh size in trawls have been in force in both areas for some years. These were successful in providing a greater yield from each year-class of groundfish as it appeared, but could not by themselves ensure a breeding stock adequate for optimum reproduction. Problems of allocation of quotas, of enforcement, and of national claims for the extension of exclusive fishing zones will require continued discussion and goodwill among the nations in the years ahead.

scholarly journals ESTUDIO DE LAS POBLACIONES DE CABALLITOS DE MAR EN DOS ZONAS DE LA COSTA NORTE DE LA HABANA Y PINAR DEL RÍO, CUBA

2011 ◽  
Vol 3 ◽  
pp. 171 ◽  
Author(s):  
Lourdes Pastor Gutiérrez ◽  
Yuliet Piloto Cubero ◽  
Raúl Igor Corrada Wong ◽  
Pedro Pablo Chevalier Monteagudo
Keyword(s):  
Abundant Species ◽  
North Coast ◽  
Visual Census ◽  
Male And Female ◽  
The North ◽  
Hippocampus Erectus ◽  
Dry Seasons ◽  
Del Rio ◽  
Expected Proportion

Se presentan los resultados sobre el estudio de las poblaciones de caballitos de mar en dos estaciones ubicadas en la costa norte de La Habana y Pinar del Río, Cuba. Se llevaron a cabo censos visuales mediante buceo libre, utilizando el método de transectos lineales, entre los meses de abril del 2004 y junio del 2005. Se obtuvieron la densidad media para las especies Hippocampus reidi (Ginsburg, 1933) e Hippocampus erectus (Perry, 1810), así como la densidad media por estaciones y por época del año. La especie H. reidi fue la más abundante y la mayor densidad se encontró en la estación de Las Cuarenta 0.0109 ind/m2. No se encontraron diferencias entre la densidad en época de lluvia y seca para las especies. Los machos y las hembras de H. reidi mostraron tallas similares (LT). Se supone un comportamiento monógamo de la especie H. reidi, debido a la proporción sexual encontrada, muy similar a la proporción esperada de 1:1. ABSTRACT This paper presents the results of the study on seahorse populations at two stations located in the north coast of La Habana and Pinar del Río, Cuba. Visual census were conducted by free divers, using the linear transect method between April 2004 and June 2005. Mean density was obtained for the species Hippocampus reidi (Ginsburg, 1933) and Hippocampus erectus (Perry, 1810), by stations and by seasons of the year. H. reidi was the most abundant species and the biggest density was present in Las Cuarenta station 0.0109 ind/m2. No differences were found regarding density between the rainy and dry seasons for the studied species. Male and female H. reidi showed similar sizes (LT). A monogamous behavior of the species H. reidi is inferred due to the sexual proportion found, which is very similar to the expected proportion of 1:1

scholarly journals A comparison of barometrical measurement, with the trigonometrical determinatiion of a height at Spitzbergen

1833 ◽  
Vol 2 ◽  
pp. 217-217
Keyword(s):  
North Coast ◽  
Comparative Measurement ◽  
North East ◽  
The North ◽  
East End ◽  
The Hill

The hill selected for this comparative measurement was the highest within convenient distance, of which the ascent was practicable, on the western part of the north coast of Spitzbergen. The summit was less than two miles from the observatory, in a direction nearly due south, the observatory being upon an island rather more than a mile from the main land. In consequence of the extreme inaccuracy of the chart of Fair Haven, published in Captain Phipps’s voyage, the author has annexed to this paper a sketch of the harbour and adjacent coast, to show the positions of the hill and observatory. The small bay formed by the shore of the main land, to the north-east end of the hill, being frozen over, afforded a perfectly level base, and corrections for inequality were thus rendered unnecessary. A polished copper cone was fixed upon a staff at the summit of the hill, the apex of which was proposed as the height to be measured: it stood 44 inches above the highest pinnacle of the summit. Captain Sabine then enters into the details of this trigonometrical measurement, from which the altitude of the cone is considered as equal to 1644 feet. The author next proceeds to detail the particulars of the barometrical measurement, and the precautions taken to insure accuracy in the instruments, and in their employment; and the height of the cone thus ascertained was 1640·07 feet. Captain Sabine concludes this paper with some remarks upon the incorrectness with which the heights of the hills on this coast are set down in Captain Phipps’s voyage.

The riebeckite-bearing dikes of Shetland (With Plate III)

1950 ◽  
Vol 29 (211) ◽  
pp. 359-373 ◽  
Author(s):  
James Phemister ◽  
C. O. Harvey ◽  
P. A. Sabine
Keyword(s):  
Basic Rock ◽  
North Coast ◽  
Green Colour ◽  
North East ◽  
The North ◽  
Metamorphic Series

The peninsula in which the mainland of Shetland ends north of Ronas Voe and Colla Firth is occupied mainly by the Ronas Hill Granite. This body is intrusive into a metamorphic series consisting of orthogneiss on the north and paragneiss oil the north-east, east, and south-east of tile peninsula. It is a biotite-granophyre within which earlier bodies of basic rock varying from diorite to gabbro are found. It is unsheared and unfoliated and is cut by a swarm of dikes with north-south trend which extends from tile north coast to Ronas Voe. There is evidence also of the existence of dikes earlier than the granite. The later dikes comprise spessartine, microdiorite, porphyrite, quartzfelspar- porphyry, and a great variety of felsites which are generally granophyric and spherulitic. Many of the felsites contain riebeckite and aegirine and have a corresponding blue or blue-green colour. From observation of chilling of dike against dike and intersection of dike by dike it has been found that tile basic dikes, spessartine, microdiorite, and porphyrite, are the oldest of the suite, the quartz-felspar-porphyries are older than the felsites, and the blue riebeckite-felsites are younger than white, pink, and dull red felsites which contain neither aegirine nor riebeckite

The Cretaceous Limestones of Jamaica and their Mollusca

1924 ◽  
Vol 61 (9) ◽  
pp. 385-410 ◽  
Author(s):  
C. T. Trechmann
Keyword(s):  
East Coast ◽  
North Coast ◽  
Lower Eocene ◽  
North West ◽  
Blue Mountain ◽  
North East ◽  
The North ◽  
Carbonaceous Shales ◽  
Green Island ◽  
Sea Coast

Most of the exposures of Cretaceous Limestone in Jamaica were faithfully indicated on the Geological Survey map of Sawkins and Brown in 1865. They are limited in extent and occur at certain places among the complex of the older or Blue Mountain series of rocks that project from beneath the covering of White Limestone that covers the greater part of the Island. Contrary to one's common experience in many European countries the Cretaceous beds in Jamaica do not approach the sea coast in any part except near Port Antonio on the north-east coast, where the Trappean shales reach the sea; near St. Ann's Bay, about the centre; and at Green Island, on the north-west coast, where the Barrettia Limestone occurs within 2 miles of the sea. Elsewhere the sea coast is occupied by the White Limestone or beds that overlie it, with the exception of stretches along the north coast around Lucea Harbour and between Port Maria and Annotta Bay, occupied by the Carbonaceous Shales of Lower Eocene age.

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