National Committee on Marine Sciences (NCMS)
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- Metabolic responses of the scleractinian coral Porites cylindrica Dana to water motion. I. Oxygen flux studiesRex, Augustus; Montebon, F.; Yap, Helen T. (Elsevier, 1995-03)Nubbins of Porites cylindrica Dana collected from a shallow reef flat in the northwestern Philippines were studied for water motion effects. Specimens were maintained in field and laboratory high (HWM) and low (LWM) water motion setups. The average maintenance times were 93 and 77 days for the field and laboratory study, respectively, which were carried out in tandem. After each maintenance period, oxygen fluxes of the corals were measured with increasing stirring rates in a laboratory flow-through respirometry system under a constant light intensity. Photosynthesis-irradiance (P-I) curves were also determined for the laboratory maintained nubbins as well as for a set of control nubbins which were kept in the collection site for 71 days. In both HWM and LWM corals, maximum rates of net photosynthesis (NP) and respiration (R) were achieved upon increasing stirring rates or turbulence to a certain level, indicating that the boundary layer limiting oxygen diffusion had been reduced to a minimum. The LWM corals attained maximum photosynthetic rates at lower rates of water motion, suggesting greater photosynthetic efficiency at lower levels of turbulence than their HWM counterparts. Profiles of NP and R with increasing stirring rates were consistently depressed for the LWM corals. Significant differences between the HWM and LWM treatments were detected in the NP profiles of the field maintained corals and in the R profiles of the laboratory maintained nubbins. The small yet significant difference in the NP profiles of the field HWM and LWM corals was attributed to the subsaturating irradiance used in the laboratory measurements because P-I curves of the laboratory maintained corals showed a large and significant difference between water motion treatments (HWM > LWM) at higher irradiances. While exhibiting lower photosynthetic rates, LWM corals had proportionally lower respiration rates resulting in P:R values very close to those of the HWM corals. Results suggest that Porites cylindrica is able to maintain its metabolic efficiency despite changes in the water motion regime.
- ₱12.3-M tilapia lost in Taal Lake fish kill: BFAR monitoring waters off 3 lakeshore townsCinco, Maricar (Philippine Daily Inquirer, Inc., 2019-06-01)At least 150 tons or P12.3 million worth of cultured tilapia turned belly-up in fish cages in Taal Lake in Batangas province due to a low level of dissolved oxygen in the water. The Department of Environment and Natural Resources and the local government of Laurel town in Batangas continued to closely monitor the remaining fish cages after the fish kill occurred in the villages of Gulod and Buso-buso in the last two days. As of Friday, provincial environment officer, Jose Elmer Bascos, said they had yet to dispose all of the dead fish as they needed a larger area to bury them.
- Who killed the milkfish?Cardinoza, Gabriel (Philippine Daily Inquirer, Inc., 2011-06-08)They're stubborn. These are the words of Nestor Domenden, regional director of the Bureau of Fisheries and Aquatic Resources (BFAR) when asked why fishkills have been a recurring nightmare in Bolinao and Anda towns in western Pangasinan in the last 10 years. “They (milkfish growers) know where their fishing structures should be built, but they continued to disregard it,” Domenden says. A report from the office of the provincial agriculturist in Lingayen shows that 72 of the 75 fishkill-hit cages were built in the waters off Catubig Point in Barangay Tara up to Barangay Culang in Bolinao, while the rest, mostly bamboo pens, dotted the fishing area from Barangay Mal-ong to Barangay Awag and across the Kakiputan Channel to the island village of Siapar in Anda.