Cerro Ballena is a fossiliferous locality of the Bahía Inglesa Formation, located in the Atacama Desert along the Pan-American Highway a few kilometers north of the port of Caldera, Chile. It has been dated back to the Late Miocene epoch, during the Neogene period. The locality was first noted in 1965 during military work and fully excavated and studied between 2011 and 2012, and is protected by law since the latter year.

A harmful algal bloom (HAB), or excessive algae growth, is an algal bloom that causes negative impacts to other organisms by production of natural algae-produced toxins, mechanical damage to other organisms, or by other means. HABs are sometimes defined as only those algal blooms that produce toxins, and sometimes as any algal bloom that can result in severely lower oxygen levels in natural waters, killing organisms in marine or fresh waters. Blooms can last from a few days to many months. After the bloom dies, the microbes that decompose the dead algae use up more of the oxygen, generating a "dead zone" which can cause fish die-offs. When these zones cover a large area for an extended period of time, neither fish nor plants are able to survive. Harmful algal blooms in marine environments are often called "red tides".