Accretion — The gradual build-up of sediment, sand, or other material over time.

Adaptation — A characteristic or behaviour that helps an organism survive and reproduce in its environment.

Algal Bloom — A rapid increase in algae in a waterbody, often caused by excess nutrients.

Apex Predator — A predator at the top of the food chain with no natural predators.

Biodiversity — The variety of living species within an ecosystem or region.

Bioaccumulation — The build-up of substances, such as pollutants, within an organism over time.

Bioindicator — A species whose presence, absence, or condition provides information about environmental health.

Bioluminescence — The production of light by a living organism through a chemical reaction.

Blue Carbon — Carbon captured and stored by coastal ecosystems such as mangroves, salt marshes, and seagrass meadows.

Bycatch — Marine animals unintentionally caught during fishing operations.

Carbon Sequestration — The process of capturing and storing carbon from the atmosphere.

Carbon Sink — A natural system that absorbs more carbon than it releases.

Carbon Storage — The capture and holding of carbon within plants, soils, sediments, or ecosystems.

Climate — The long-term average weather patterns of a region.

Conservation Status — A measure of a species’ risk of extinction.

Coral Bleaching — The loss of algae from coral tissue, causing corals to turn white and become stressed.

Deep Sea — The part of the ocean below the reach of sunlight, typically deeper than 200 metres.

Decomposition — The breakdown of dead plants, animals, and organic matter by bacteria, fungi, and other organisms.

Detritus — Dead organic material, such as decaying plants, animals, and waste, that provides food for many organisms.

Echolocation — The use of sound waves and returning echoes to locate objects or navigate.

Ecotourism — Responsible travel that supports conservation and local communities.

El Niño — A climate pattern that warms parts of the Pacific Ocean and influences global weather.

Endangered Species — A species facing a very high risk of extinction in the wild.

Endemic Species — A species found naturally in only one specific location or region.

Erosion — The wearing away and movement of soil, sand, or rock by wind, water, or other forces.

Estuary — A coastal area where freshwater from rivers mixes with seawater.

Eutrophication — Excess nutrients in a waterbody that can lead to algal blooms and reduced oxygen levels.

Filter Feeder — An animal that feeds by filtering food particles from the water.

Food Chain — A sequence showing how energy passes from one organism to another through feeding.

Food Web — A network of interconnected food chains within an ecosystem.

Ghost Fishing — The continued capture of marine life by lost or discarded fishing gear.

Greenhouse Gas — A gas that traps heat in the atmosphere and contributes to warming.

Greenwashing — Misleading claims that make an organisation or product appear more environmentally friendly than it is.

Habitat Fragmentation — The breaking up of habitats into smaller, isolated areas.

Indicator Species — A species that reflects the condition of its environment.

Intertidal Zone — The area of shoreline exposed at low tide and covered at high tide.

Invasive Species — A non-native species that spreads and causes harm to an ecosystem.

Keystone Species — A species that has a disproportionately large effect on its ecosystem.

Lagoon — A shallow body of water separated from the ocean by reefs, sandbars, or islands.

La Niña — A climate pattern that cools parts of the Pacific Ocean and influences global weather.

Mangrove — A salt-tolerant tree or shrub that grows in coastal areas and helps protect shorelines while supporting diverse marine life.

Marine Heatwave — A period of unusually warm ocean temperatures lasting days, weeks, or longer.

Marine Megafauna — Large marine animals such as whales, sharks, turtles, and rays.

Marine Snow — A continuous fall of organic material, including dead plankton, waste, and other particles, from surface waters to the deep ocean.

Metamorphosis — A major change in body form that occurs during an animal’s life cycle.

Microplastics — Small plastic particles less than 5 mm in size.

Migration — The regular movement of animals between different locations, often linked to feeding, breeding, or seasonal changes.

Mutualism — A relationship in which both species benefit.

No-Take Zone — A protected area where fishing and the removal of marine life are prohibited.

Nursery Habitat — An area where young animals grow and develop before moving into adult habitats.

Nutrient Cycling — The movement and reuse of nutrients through an ecosystem.

Ocean Acidification — The ongoing decrease in ocean pH caused by the absorption of carbon dioxide.

Ocean Deoxygenation — The gradual decline of oxygen levels in the ocean.

Ocean Warming — The long-term increase in ocean temperatures.

Oviparous — Producing offspring by laying eggs outside the body.

Ovoviviparous — Producing eggs that hatch inside the parent before birth.

Overfishing — Catching fish faster than populations can replace themselves.

Pelagic — Relating to the open ocean away from the seafloor and coastline.

Photosynthesis — The process by which plants and algae use sunlight to produce energy.

Protected Species — A species legally protected from activities such as hunting, collecting, or trade.

Rehabilitation — Actions taken to improve the condition of a damaged ecosystem.

Resilience — The ability of an ecosystem to resist or recover from disturbance.

Restoration — The process of returning a damaged ecosystem closer to its natural state.

Rewilding — Restoring natural processes, habitats, or species to an ecosystem.

Sedimentation — The settling and accumulation of sediment in an area.

Species Richness — The number of different species present in an area.

Spawning — The release of eggs and sperm for reproduction.

Subtropical — Relating to regions between the tropical and temperate zones, typically characterised by warm temperatures and seasonal variation.

Sustainability — Using resources in a way that meets current needs without compromising the future.

Symbiosis — A close relationship between two different species.

Temperate — Relating to regions with moderate temperatures and distinct seasonal changes.

Thermocline — A layer in the ocean where temperature changes rapidly with depth.

Threatened Species — A species considered at risk of becoming endangered.

Tropical — Relating to warm regions near the equator that experience little seasonal temperature variation.

Trophic Cascade — Ecological changes caused by the addition or removal of species at different trophic levels.

Trophic Level — An organism’s position within a food chain or food web.

Trophic Structure — The arrangement of feeding relationships within an ecosystem.

Upwelling — The movement of deep, nutrient-rich water toward the ocean surface.

Viviparous — Producing live young that develop inside the parent.

Zooxanthellae — Microscopic algae that live within coral tissue and provide energy through photosynthesis.