Simplyphytoplankton - Simply Phytoplankton

Leighton Lum

Aphid captured under a student microscope.

What’s one of the best places in the world to find white sharks?

Greater Farallones National Marine Sanctuary.

Located in California north and west of San Francisco, the sanctuary is home to one of the most significant populations of white sharks on the planet. The waters around the Farallon Islands in particular provide critical feeding areas for the sharks’ annual migration.

So how do researchers in the sanctuary study the sharks? One way is to use a decoy shaped like a seal with a GoPro attached. When the shark investigates the decoy, the researchers can get the images they need to identify the shark.

Learn more about white sharks in Greater Farallones National Marine Sanctuary on the sanctuary’s website and in our video:

EXPLAINED WHY WHALE SHARKS CONGREGATE IN JUST 20 LOCALITIES WORLDWIDE

We know whale sharks (Rhincodon typus), the biggest fish in the world, aggregate at just 20 coastal locations globally.  Why these animals, which can reach more than 18 m in length, choose these specific places, has perplexed researchers and conservationists. Although whale-shark aggregations had been recorded near tropics, including Mozambique, the Maldives, Honduras, Australia and others places, what causes these aggregations remain unknow.

Aggregations typically occur in the fore reef and lagoon areas, leading out to the reef slope, reef wall or continental slope, which has a steeper slope, leading whale sharks to deep-sea environment. Researchers sugests whale shark can filter food at greath depths, where the water is cold, and then bask in the sun at shallow depths, warming their cold-blooded bodies, as they depend on external sources of body heat.

-  Location of aggregation and non-aggregation sites. Hotspots are in red.

These places are very productive, where plankton and small crustaceans abound. However, sharks swimming in shallow waters near the surface are vulnerable to accidents caused by vessels, as tourist boats which approaches them. The whale shark is considered Vulnerable on the IUCN Red List, these findings increase our understanding of whale shark behaviour and may help guide the identification and conservation of further aggregation sites.

Photo by  Abe Khao Lak

Copping et al., 2018.  Does bathymetry drive coastal whale shark (Rhincodon typus) aggregations?  Aquatic Biology section

Migaloo is an albino humpback whale,  usually sighted along the Australian coast,  and occasionally in New Zealand waters.  Migaloo was named by the Hervey Bay local aboriginal collective,  and it means “white fella”.  While several Humpback Whales have been spotted with almost 90% white pigment coverage,  Migaloo is the only documented albino.

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- Shadows of the ocean.🐋 Photo: @itookthisphotograph #oceanfilmtour #oceanlovers #underwaterphoto #whale #oceanlife #marinelife #ocean

Top: The Central Bank of Costa Rica in the capital, San José.

Middle: Fountain in San José.

Bottom: Statue of a worker in San José.

Bioluminescent Dinoflagellates

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