Bait shrimp fishery of Biscayne Bay

A small but valuable live bait shrimp fishery has existed in Biscayne Bay since at least the early 1950s. In recent years there has been increasing pressure from recreational fishing and environmental groups to eliminate this fishery from the Bay because the fishing activity is generally thought to be deleterious to the environment and/or destructive to juvenile game fish. This study was initiated to update the existing knowledge of the bait shrimp fishery in Biscayne Bay and document historical trends in number of participants, fishing methods, fishing area, seasonality, total catch, catch-per-unit-effort, disposition of the catch, and economics of the industry. (21pp.

Recent Advances in the Management of Marine Protected Areas in the Philippines

This study presents recent advances in the management of Marine Protected Areas (MPAs) in the Philippine from the mid-1970s, when the first MPA was established, to the present. At present, there are over 1300 established and proposed MPAs in the country. More than 50% of these are less than 10ha in size. As a result, less than 2% of the country’s reef areas are under some level of protection, which is believed to be too low for protective measures to have an impact. In terms of management, only 10-15% of established MPAs are effectively managed. Several challenges are posed by these major shortcomings. Two approaches have recently been initiated to address these. The MPA Support Network (MSN) was recently established to link various efforts and initiatives in managing MPAs in the different regions of the country. There are also recent efforts of developing schemes for truly science-based establishment of MPA networks

Diel patterns in abundance, distribution and composition of ichthyoplankton in shallow reef areas in Southern Guimaras, Central Philippines

Ichthyoplankton samples from 20 reef stations were collected in Southern Guimaras, Central Philippines, during the day and night by means of 5 minute surface horizontal tows using a rectangular plankton net with a 300μm mesh bag attached to it. Overall mean ichthyoplankton density at night (168ind/100m^3) was three times more than that during the day (56ind/100m^3), while taxon richness (family level) was 50% higher at night. These results are compared with observed diel patterns in other investigations. Diel differences in overall egg and larval densities and composition are related to the station location, substrate and other factors. The relative similarity in day-night patterns in stations over deep water suggests that the substrates (seagrass beds and coral reefs) serve as shelters from predation during the daytime

Growth, survival, proximate and fatty acid composition of sandworm Perinereis quatrefagesi (Grube, 1878) fed variable feed types

Abstract only.Sandworm Perinereis quatrefagesi has been used as feed for crustacean broodstock due to its reproductive-enhancing properties particularly protein and highly unsaturated fatty acids (HUFAs). Juvenile sandworms collected along the coast of Guimbal, Iloilo were reared in tanks and fed three nutritionally variable feed types: fish fecal waste, fish meal and rice bran. After 56 days, feeds affected (p-1 dry weight. High crude protein fish meal promoted better (p-1) than fish feces (1.2~c0.3% day-1) and rice bran (1.1~c0.3 % day-1). However, crude fat content of sandworm was higher (p-1) than in fecal waste (13.6~c2.9 g 100 g-1) and fish meal (10.5~c3.1 g 100 g-1) treatments. Levels of highly unsaturated fatty acids (HUFAs) such as 20:4 n-6, 22:6 n-3 and 20:5 n-3 did not differ significantly (p>0.05) at 0.41~c0.21 to 0.89~c0.51 g 100 g-1, 0.21~c0.24 to 0.43~c0.22 g 100 g-1 and 0.57~c0.46 to 0.88~c0.31 g 100 g-1, respectively. The study demonstrated that P. quatrefagesi: (1) can survive well in nutritionally variable feed types although it grows better in high protein diet; (2) crude protein levels were high regardless of feed types; and (3) crude fat content was high in high fat diet but n-3 and n-6 HUFAs were not significantly different regardless of feed types

Phylogeography of the planktonic shrimp Lucifer hanseni Nobili 1905 in the Indo-Malayan Archipelago

Using partial sequences of two mitochondrial genes, cytochrome c oxidase subunit I (COI) and 12S ribosomal RNA (12S rRNA), and one nuclear gene, 28S ribosomal RNA (28S rRNA), we investigated population genetics of the holoplanktonic shrimp Lucifer hanseni Nobili, 1905 in the Indo-Malayan Archipelago (IMA), encompassing Andaman Sea, Malacca Strait, Gulf of Thailand, Borneo Island, Philippines (hereafter collectively referred to as the Thailand-Malaysia-Philippine area: TMP), Celebes Sea (CS), and the waters near islands in the Western Pacific (WP) including Palau, Papua New Guinea and Solomon Islands. The samples from the TMP showed the highest number of haplotypes. Significant phylogeographic structure was found in the L. hanseni populations (ΦST = 0.832 for COI, 0.159 for 12S rRNA, 0.783 for 28S rRNA). The total number of haplotypes was 46 in COI, 28 in 12S rRNA and 23 in 28S rRNA. The haplotype network analyses revealed two major clades for COI (subgroups: TMP + CS, WP) and for 12S rRNA and 28S rRNA (TMP, CS + WP). The CS and WP populations appeared isolated from the TMP populations. The samples from the CS showed low genetic diversity compared with the other samples at both haplotype and nucleotide levels, suggesting that the population CS experienced bottleneck events. This is the first demonstration of significant genetic structure of a holoplanktonic metazoan in IMA, which is suggested to be synergistically influenced by historical events (vicariance) and contemporary oceanographic circulations and corroborates the results of previous studies on other benthic/demersal animals with mero-planktonic phases

Diel patterns in abundance, distribution and composition of ichthyoplankton in shallow reef areas in Southern Guimaras, Central Philippines

Ichthyoplankton samples from 20 reef stations were collected in Southern Guimaras, Central Philippines, during the day and night by means of 5 minute surface horizontal tows using a rectangular plankton net with a 300μm mesh bag attached to it. Overall mean ichthyoplankton density at night (168ind/100m^3) was three times more than that during the day (56ind/100m^3), while taxon richness (family level) was 50% higher at night. These results are compared with observed diel patterns in other investigations. Diel differences in overall egg and larval densities and composition are related to the station location, substrate and other factors. The relative similarity in day-night patterns in stations over deep water suggests that the substrates (seagrass beds and coral reefs) serve as shelters from predation during the daytime

Some Aspects of the Population Biology of the Green Tiger Prawn Penaeus semisulcatus (De Haan, 1844) from Pilar and Capiz Bays, Northern Panay, West Central Philippines

This study is a first report on the population biology of the green tiger prawn Penaeus semisulcatus (de Haan) from northern Panay, west central Philippines. The study was conducted for eight months (May to December 2002) whereby total lengths of both male and female P. semisulcatus of various sizes were measured monthly from the catches of municipal trawlers operating at Pilar and Capiz Bays. Based on the Bhattacharya method, a mean growth rate of 0.78 ± 0.28 and 1.45 ± 0.39 mm/day were estimated for males and females, respectively. Using the ELEFAN I method, growth parameters derived for males were L∞ = 263 mm, k = 0.7/yr and a growth index (Ø') of 4.69. On the other hand, growth parameters derived for females were L∞ = 271 mm, k = 1.6/yr and a growth index (Ø') of 5.07.Based on length-converted catch curve analysis, the total mortality (Z) of the male population is estimated to be 3.61/yr while that of the females is 5.65/yr. Male prawns showed a higher exploitation rate (0.53) compared to that of the females (0.35) indicating the susceptibility of males to fishing. This study also revealed that trawlers in Pilar and Capiz Bays are already getting small sizes of prawns, without allowing them to reach sexual maturity. Hence, there is a need to increase the present mesh size (2.5 cm) of the cod end of trawls in order to avoid growth overfishing, which may occur with continued increase in fishing effort. Furthermore, the recruitment pattern showed two pulses of unequal strengths and time, dividing the year into a 7-5 month pattern. The said pattern, especially for females, may have resulted from a major and minor spawning peak of the said species during the months of June-September and January