In our previous issues—Endangered Cultural Heritage Sites in Latin America, Part II
and Endangered Cultural Heritage Sites in Latin America —we explored six of the seven endangered sites across the region. These features aim to highlight the extraordinary cultural and natural wealth of Latin America, while drawing attention to the challenges many of these sites currently face—often without widespread recognition. As we complete this series, we turn to the final site identified by UNESCO, the Islands and Protected Areas of the Gulf of California in Mexico. 

The Gulf of California in northwestern Mexico—once famously described as the “Aquarium of the World”—is widely recognized as a site of outstanding global importance for marine conservation. This serial property comprises 244 islands, islets, and coastal areas set within a dramatic landscape of rugged cliffs, sandy beaches, and desert shores, all bordered by striking turquoise waters. The visual contrast between arid landforms and the surrounding sea contributes to the area’s exceptional natural beauty, while its biological richness places it among the most significant marine ecosystems on Earth.

The property extends from the Colorado River Delta in the north to approximately 270 kilometers southeast of the tip of the Baja California Peninsula. Covering a total area of 1,837,194 hectares, roughly one quarter of which is terrestrial and the remainder marine, it includes eight major island groups as well as nine additional protected areas encompassing coastal and marine zones. This vast and varied territory contains a remarkable range of habitats, from pelagic (open water column) and benthic (deep sea floor) environments to coral reefs, mudflats, coastal wetlands, and desert and deciduous forest ecosystems.

The Gulf of California is distinguished by exceptional biodiversity and a high degree of unique endemic species both on land and in the sea. The islands, most of which are of volcanic origin, support a rich desert flora, including approximately 700 species of vascular plants—an unusually high number for such environments. Among these are numerous succulents, including some of the tallest cacti in the world, exceeding 25 meters in height. Terrestrial fauna is equally notable, with around 115 species of reptiles, nearly half of them endemic, and 154 recorded species of land birds. The islands also provide critical habitat for large populations of resident and migratory birds, with some small islands supporting significant proportions of global populations of species such as Heermann’s Gull, Blue-footed Booby, and Black Storm Petrel.

Marine biodiversity is even more extraordinary. Nearly 900 species of fish have been documented, approximately 90 of which are endemic to the Gulf. The property also supports around 35% of the world’s total number of marine mammal species and about one third of all marine cetaceans. These include several species of dolphins and whales, among them the endangered blue whale and fin whale, as well as the vulnerable Sperm whale. Particularly notable is the presence of the critically endangered vaquita, or Gulf porpoise, one of the rarest marine mammals in the world. The region’s productivity sustains not only large vertebrates but also vast concentrations of macro-invertebrate life, contributing to the ecological complexity and resilience of the system. The coral reef at Cabo Pulmo stands out as one of the most important reef systems in the eastern Pacific.

The property is also remarkable for the diversity of its island types and their ecological histories. Some islands are “bridge islands,” which were once connected to the mainland during periods of lower sea levels, allowing species to colonize them over land before becoming isolated. Others are truly oceanic islands, never connected to the mainland and populated only by species capable of crossing water barriers by air or sea. This combination has resulted in distinct evolutionary pathways and contributes significantly to the region’s biodiversity.

In addition to its ecological significance, the Gulf of California possesses outstanding scenic value. The interplay of desert landscapes, rugged islands, and clear, reflective waters creates a setting of exceptional visual impact. Beneath the surface, unusual water transparency and complex submarine topography create conditions that have made the region a globally renowned destination for diving.

Most of the marine area and the majority of the islands are federally owned and largely uninhabited, although some contain small settlements and seasonal fishing camps. Isla María Madre has served as a state penitentiary since 1905, while Isla Tiburón—the largest island in the Gulf—is communally owned by the Seri Indigenous people, who regard it as a sacred site and continue to carry out traditional ceremonies there.

The region has a long history of human use. Coastal areas and larger islands were historically inhabited prior to the decline of Indigenous populations following the introduction of foreign diseases. In more recent centuries, activities such as guano and egg collection, hunting of sea lions, and whaling took place throughout the Gulf. Most of these practices have since been discontinued, allowing many ecosystems to recover naturally. However, contemporary pressures remain significant.

The most serious threats to the integrity of the Gulf’s ecosystems originate both within and beyond the protected areas. Overfishing—whether artisanal, industrial, or recreational—represents the most persistent challenge to marine conservation, requiring careful management to ensure that harvesting levels remain sustainable. Additional pressures include coastal development, expanding tourism, and pollution from agriculture.

The conservation of the Gulf of California has a formal history dating back to at least the 1950s, and all islands within the property are protected under Mexican environmental legislation. Management is overseen by the National Commission for Natural Protected Areas (CONANP), in coordination with other governmental bodies and supported by numerous national and international organizations. Despite these efforts, significant challenges remain, including the need for long-term funding and effective coordination across multiple jurisdictions with differing conservation statuses.

The Gulf of California stands as a global priority for biodiversity conservation and a resource of immense scientific and economic value. Its ecosystems support fisheries and tourism that are vital to regional livelihoods, while its extraordinary biological richness offers unparalleled opportunities for research and environmental education. Ensuring the continued protection of this unique marine and terrestrial landscape is essential not only for preserving its natural heritage but also for sustaining the ecological productivity and economic benefits upon which local communities depend.

Without awareness, meaningful action is unlikely to follow. We commend UNESCO and other organizations for bringing global attention to these places. The risks they face should never be overlooked or treated as secondary; they must remain a priority if we are to protect these sites and understand the challenges they face.

References:

Islands and Protected Areas of the Gulf of California
https://whc.unesco.org/en/list/1182

Islands and Protected Areas of the Gulf of California
https://www.ebsco.com/research-starters/social-sciences-and-humanities/islands-and-protected-areas-gulf-california