Montipora calcarea

Montipora calcarea is a colonial stony coral in the family Acroporidae, typically forming encrusting to plate-like or laminar colonies. Like other scleractinian corals, its polyps host symbiotic zooxanthellae, algae that supply the coral with energy through photosynthesis while the coral builds a calcium carbonate skeleton. This growth contributes to the physical structure of reef systems, providing habitat and shelter for fish and invertebrates and playing a role in overall reef accretion and stability.

The species occurs in the Indo-Pacific region, with records from Australia, Papua New Guinea, the Philippines, Madagascar, Malaysia, Thailand, and Brunei. It inhabits marine neritic waters, generally in shallow reef environments where sufficient light penetrates to support its photosynthetic symbionts.

Montipora calcarea faces a combination of pressures common to reef-building corals across its range. Fishing and harvesting activities, along with recreational use of reef areas, contribute to direct physical damage and resource extraction. Land-based pollution, including domestic and urban wastewater and runoff from agricultural and forestry operations, degrades water quality, while sediment and nutrient loading from non-timber crop cultivation compounds this stress.

The species is also affected by invasive species, disease, and competition or predation from problematic native species, as well as broader habitat shifting linked to changing environmental conditions.

Conservation efforts affecting this species are largely embedded in broader coral reef protection frameworks, including marine protected areas, fisheries management, and water quality regulations within its range countries, alongside international monitoring under the IUCN Red List.

The population is currently assessed as Endangered with a decreasing trend. Given the persistence of multiple concurrent, unresolved threats, the species' outlook remains one of continued decline absent substantial reductions in cumulative pressures.