National Committee on Marine Sciences (NCMS)
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- Connections and clustering of Paralytic Shellfish Toxin events among coastal embayments in an archipelago partly mediated by advectionPunongbayan, Andalus T.; Wang, Ysabel D.; Villanoy, Cesar L.; Yñiguez, Aletta T. (Elsevier, 2022-01)The potential for advection to influence harmful algal bloom (HAB) spread in adjacent embayments and islands has not been investigated in the Philippines as previous studies have focused on HAB dynamics within specific embayments. Advection of HABs may be relevant in the Samar-Leyte region where adjacent sites are subject to recurrent blooms of Pyrodinium bahamense. We used different analyses to extract the potential role of advection in blooms in the region. First, we used Bayesian and information theoretic approaches applied to historical data on shellfish bans to quantify spatial dependencies in HAB occurrences between sites. Then, to determine whether such dependencies are related to circulation patterns in the region, we analyzed connectivity using a hydrodynamic model coupled with a conservative tracer-based HAB model. The Bayesian network showed that in 7 out of 11 sites, the probability of a shellfish ban depended on the state of an adjacent site. Site pairs with direct dependence relations also shared relatively high similarity in HAB occurrences over time. In the modelled network, bans tend to occur sequentially, spreading from a few sites with relatively high probabilities for ban events. A subset of sites (sources) were found to be informative of future HAB event probabilities in other sites (destinations) over time lags that are generally longer the farther the destination. Modelled surface advection showed high connectivity strengths between sources and destinations associated with circulation features, e.g., an anticyclonic current in Leyte, wind-driven coastal current in western Samar, and tidally-driven flow in the shallow embayments in southwest Samar. High connectivities were correlated with direct dependence relations in the Bayesian network. Connectivity explained up to about 1/3 of the variance in statistical dependencies between ban signals. Our results show that Paralytic Shellfish Toxin events within this region can be due to advection of blooms originating from nearby areas rather than localized cyst dynamics within an embayment. Particular sites were also identified as potential indicator sites within spatial clusters for monitoring since they are typically where blooms originate and spread from.
- Shellfish ban up in 10 VisMin areasCariaso, Bella (Philippine Star Printing Co., Inc., 2024-10-01)Ten bodies of water in the Visayas and Mindanao remain affected by the paralytic shellfish poison or red tide toxin, according to the Bureau of Fisheries and Aquatic Resources. The BFAR said a shellfish ban has been imposed on Carigara Bay in Leyte
- Red tide invades 4 Samar bays anewManuel, Elmer (Concept & Information Group, Inc., 2023-12-02)The Bureau of Fisheries and Aquatic Resources on Friday reported the presence of red tide in Cambatutay Bay in Samar based on the latest examination of meat samples. The agency revealed that seawater samples collected in Cambatutay Bay have tested positive for red tide since 23 Oct 2023 but it was only on 30 November that authorities found the presence of toxins in shellfish meat.
- Red tide invades Samar bays anew(Concept & Information Group, Inc., 2023-10-07)The Bureau of Fisheries and Aquatic Resources on Friday revealed that the red tide phenomenon has recurred in three bays in Samar and Eastern Samar provinces, raising warning not to consume shellfish products in these areas. In a statement, the BFAR identified the bays as Irong-Irong Bay in Catbalogan City, Samar, coastal waters of Calbayog City, Samar; and Matarinao Bay in Eastern Samar province. The bloom of this toxic organism returned in Matarinao after three weeks of red tide absence and in Irong-Irong Bay after nine months. The coastal water of Calbayog City was included in the red tide watch in early 2022.
- 3 bays in Samar placed on red tide alertGabieta, Joey (Philippine Daily Inquirer, Inc., 2023-10-08)The Bureau of Fisheries and Aquatic Resources (BFAR) has warned the public not to consume shellfish products taken from three bays on Samar Island where the red tide toxin was detected. “To safeguard human lives, we are issuing this warning as a precautionary advice to the public to refrain from gathering, selling, and eating all types of shellfish and Acetes sp. locally known as ‘alamang’ or ‘hipon’ from these bays,” said BFAR in its local shellfish bulletin on Friday. According to BFAR, affected by the red tide toxin were the Irong-Irong Bay in Catbalogan City, Samar province
- Capiz waters now red tide-freeTayona, Glenda (Panay News, Inc., 2023-02-24)Good news for fisherfolks in this province. After several months, the coastal waters in Panay, President Roxas, and Pilar towns are finally free from paralytic shellfish poison (PSP) or toxic red tide, according to Bureau of Fisheries and Aquatic Resources (BFAR) Shellfish Bulletin No. 06-2023.
- Red tide still present in three Capiz townsCelino, Felipe (Daily Guardian Multi-Media Services, Inc., 2023-01-23)Paralytic Shellfish Poison or red tide toxin is still present in the waters of three Capiz towns. Based on the latest shellfish bulletin issued by the Bureau of Fisheries and Aquatic Resources (BFAR)-6, the toxicity level is still high in Panay, Pres. Roxas and Pilar. The coastal waters of Sapian Bay (Sapian and Ivisan) including Roxas City are red tide-free.
- Red tide warning lifted in parts of Western Samar, LeyteOchave, Revin Mickhael D. (BusinessWorld Publishing Corporation, 2021-06-25)The Bureau of Fisheries and Aquatic Resources (BFAR) declared parts of Western Samar and Leyte free from red tide contamination based on the latest test results. BFAR said in its 18th shellfish bulletin that red tide warnings are lifted in Zumarraga, San Pedro Bay, Maqueda Bay, and Villareal Bay in Western Samar, and Carigara Bay and Ormoc Bay in Leyte.
- San Pedro Bay gets red tide anewRecuerdo, Elmer (Concept & Information Group, Inc., 2021-01-30)The Bureau of Fisheries and Aquatic Resources (BFAR) in Eastern Visayas announced on Friday that the San Pedro Bay in Basey, Samar has been included in the shellfish ban following the detection of “red tide” in the bay. This comes over a month since the bay was cleared free of algae that causes paralytic shellfish poisoning. “All types of shellfish and Acetes sp. locally known as “Alamang or Hipon” gathered from the said area are not safe for human consumption” the BFAR said in its advisory issued on Friday.