• Amblyrhynchus cristatus. The IUCN Red List of Threatened Species 2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      Marine Iguanas occur on the large islands of Española, Fernandina, Floreana, Genovesa, Isabela, Marchena, Pinta, San Cristobál, Santa Cruz, Santa Fé, and Santiago, the mid-sized islands of Baltra, Bartolomé, Pinzón, Plaza Norte, Plaza Sur, Rábida, and Seymour Norte, smaller key populations on Darwin, Roca Redonda, and Wolf, as well as many satellite islets of the Galápagos Archipelago, Ecuador. The estimated extent of occurrence is 56,647 km2 by minimum convex polygon and the area of occupancy is estimated at 42,155 km2 using a 2x2 km grid overlay within a coastal buffer 2 km from the shore. The population size is poorly known and crudely estimated as low as 33,000 total iguanas after a strong El Niño famine and as many as 350,000 after several years of La Niña abundant food conditions, with fewer than 210,000 mature individuals. Current taxonomy describes eleven subspecies. Only one subspecies has a genetically resilient effective population size, and only one more is close to the threshold to be considered healthy; the remaining are critically low to moderate. Overall population trend is unknown, but is subject to extreme fluctuations and reductions during El Niño events (10–90% mortality), which are predicted to intensify in the future with ongoing climate change. Marine Iguana populations have been reduced by invasive alien predators such as feral cats, rats, and free-roaming pigs and dogs on five of the 13 main islands (ca 30% of the total population)....
    • Amblyrhynchus cristatus ssp. cristatus. The IUCN Red List of Threatened Species 2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Fernandina Marine Iguana is found on the islands of Fernandina, Isabela, Tortuga, and very likely other satellite cays in the Galápagos Islands, Ecuador. The estimated extent of occurrence is 8,845 km2 by minimum convex polygon and the area of occupancy is estimated at 2,288 km2 . The population size is poorly known and crudely estimated at 20,000–160,000 total iguanas with fewer than 96,000 mature individuals. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. This iguana is threatened by invasive alien Black Rats, feral cats, and free-roaming pigs and dogs on Isabela Island. Fernandina Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from stress, marine pollution, habitat degradation, and chance of further invasive species introductions and emergent diseases. Land-based tourist presence and intensity has been shown to have a significant overall negative effect on iguana health. The population is estimated to have been reduced by at least 20–40% over the last three generations (18–24 years) due to the impacts of invasive alien predators, oil spills and urban pollution, and cyclic feast/famine fluctuations. Without significant invasive species control, declines are projected to continue in the near future, with a per cent reduction of at least 20–40% estimated over the past two generations and one generation into the future. This subspecies qualifies for listing as Vulnerable.
    • Amblyrhynchus cristatus ssp. hassi. The IUCN Red List of Threatened Species 2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Santa Cruz Marine Iguana is found on the islands of Santa Cruz, Baltra, Seymour Norte, Plaza Sur, Plaza Norte, and very likely other satellite cays in the Galápagos Islands, Ecuador. The estimated extent of occurrence is 1,439 km2 by minimum convex polygon and the area of occupancy is estimated at 580 km2 . The population size is poorly known and crudely estimated at 2,000–13,000 total iguanas with fewer than 7,800 mature individuals. Genetic data indicate a small effective population size. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. This iguana is threatened by invasive alien Black Rats, Norway Rats, feral cats, and free-roaming pigs and dogs. Santa Cruz Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from stress, marine pollution, habitat degradation, and chance of further invasive species introductions and emergent diseases. Land-based tourist presence and intensity has been shown to have a significant overall negative effect on iguana health. The population is estimated to have been reduced by at least 30–40% over the last three generations (18–24 years) due to the impacts of invasive alien predators, oil spills, low effective population size, and cyclic feast/famine fluctuations. Without significant invasive species and pollution control, declines are projected to continue in the near future, with a percent reduction of at least 20–30% estimated over the past two generations and one generation into the future. This subspecies qualifies for listing as Endangered
    • Amblyrhynchus cristatus ssp. godzilla. The IUCN Red List of Threatened Species 2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Punta Pitt Marine Iguana is found only on the northern and eastern part of San Cristóbal Island and very likely the satellite islets in this region in the Galápagos Islands, Ecuador. The estimated extent of occurrence is 257 km2 by minimum convex polygon and the area of occupancy is estimated at 188 km2. The population size is poorly known and was crudely estimated at 50–400 total iguanas on the entire island in 2004. A more recent mark-resight study calculated 147 mature adults at the largest subpopulation of this new subspecies designation. Genetic data indicate a critically low effective population size. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. This iguana is threatened by invasive alien Black Rats, Norway Rats, feral cats, and free-roaming pigs and dogs. Punta Pitt Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from stress, marine pollution, habitat degradation, and chance of further invasive species introductions and emergent diseases. Land-based tourist presence and intensity has been shown to have a significant overall negative effect on iguana health.
    • Amblyrhynchus cristatus ssp. hayampi. The IUCN Red List of Threatened Species 2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Marchena Marine Iguana is found only on the island of Marchena in the Galápagos Islands, Ecuador. The extent of occurrence and area of occupancy is estimated at 140 km2 . The population size is poorly known and estimated at 1,000–40,000 total iguanas, with fewer than 6,000 mature individuals. Genetic data indicate a critically low effective population size. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. Marchena Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from marine pollution, habitat degradation, and chance of invasive species introductions and emergent diseases. This subspecies qualifies for listing as Endangered.
    • Amblyrhynchus cristatus ssp. jeffreysi. The IUCN Red List of Threatened Species 2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Wolf Marine Iguana is found on the islands of Wolf, Darwin, and Roca Redonda in the Galápagos Islands, Ecuador. The estimated extent of occurrence is 1,058 km2 by minimum convex polygon and the area of occupancy is estimated at 16 km2 using a 2x2 km grid overlay. The population size is poorly known and estimated at 600–2,300 total iguanas, with fewer than 1,380 mature individuals. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. Wolf Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from marine pollution, habitat degradation, and chance of invasive species introductions and emergent diseases. This subspecies qualifies for listing as Endangered.
    • Amblyrhynchus cristatus ssp. mertensi. The IUCN Red List of Threatened Species 2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The San Cristóbal Marine Iguana is found only on the southern and western part of San Cristóbal Island and very likely the satellite islets in this region in the Galápagos Islands, Ecuador. The estimated extent of occurrence is 398 km2 by minimum convex polygon and the area of occupancy is estimated at 240 km2 . The population size is poorly known and was crudely estimated at 50–400 total iguanas on San Cristóbal in 2004, although this is under-estimated as a more recent mark-resight study calculated 300 mature adults at the largest subpopulation. Genetic data indicate a critically low effective population size. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. This iguana is threatened by invasive alien Black Rats, Norway Rats, feral cats, and free-roaming pigs and dogs. San Cristóbal Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from stress, marine pollution, habitat degradation, and chance of further invasive species introductions and emergent diseases. Land-based tourist presence and intensity has been shown to have a significant overall negative effect on iguana health.
    •  Amblyrhynchus cristatus ssp. nanus. The IUCN Red List of Threatened Species 2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Genovesa Marine Iguana is found only on the island of Genovesa in the Galápagos Islands, Ecuador. The extent of occurrence and area of occupancy is estimated at 28 km2 . The population size is poorly known and estimated at 900–15,000 total iguanas, with fewer than 9,000 mature individuals. Genetic data indicate a moderate effective population size. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. Genovesa Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from marine pollution, habitat degradation, and chance of invasive species introductions and emergent diseases. Land-based tourist presence and intensity has been shown to have a significant overall negative effect on iguana health. This subspecies qualifies for listing as Critically Endangered.
    • Amblyrhynchus cristatus ssp. sielmanni. The IUCN Red List of Threatened Species2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Pinta Marine Iguana is found only on the island of Pinta in the Galápagos Islands, Ecuador. The extent of occurrence and area of occupancy is estimated at 92 km2 . The population size is poorly known and estimated at 800–6,000 total iguanas with fewer than 3,600 mature individuals. Genetic data indicate a low to moderate effective population size. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. Pinta Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from marine pollution, habitat degradation, and chance of invasive species introductions and emergent diseases. This subspecies qualifies for listing as Critically Endangered.
    • Amblyrhynchus cristatus ssp. trillmichi. The IUCN Red List of Threatened Species2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Santa Fé Marine Iguana is found only on the island of Santa Fé in the Galápagos Islands, Ecuador. The extent of occurrence and area of occupancy is estimated at 44 km2 . The population size is poorly known and estimated at 3,000–16,000 total iguanas with fewer than 9,600 mature individuals. Genetic data indicate a low to moderate effective population size. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. Santa Fé Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from marine pollution, habitat degradation, and chance of invasive species introductions and emergent diseases. Land-based tourist presence and intensity has been shown to have a significant overall negative effect on iguana health.
    • Amblyrhynchus cristatus ssp. venustissimus. The IUCN Red List of Threatened Species2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Española Marine Iguana is found on the islands of Española, Floreana, Gardner-by-Floreana, Champion, and very likely their satellite cays in the Galápagos Islands, Ecuador. The estimated extent of occurrence is 1,184 km2 by minimum convex polygon and the area of occupancy is estimated at 308 km 2 . The population size is poorly known and crudely estimated at 3,700–37,000 total iguanas with fewer than 22,200 mature individuals. Genetic data indicate a small to moderate effective population size. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. This iguana is threatened by invasive alien Black Rats, feral cats, and free-roaming pigs and dogs. Española Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from stress, marine pollution, habitat degradation, and chance of further invasive species introductions and emergent diseases. Land-based tourist presence and intensity has been shown to have a significant overall negative effect on iguana health. This subspecies qualifies for listing as Endangered.
    • Amblyrhynchus cristatus ssp. wikelskii. The IUCN Red List of Threatened Species 2020

      MacLeod, A.; Nelson, K.; Grant, Tandora D. (2020)
      The Santiago Marine Iguana is found on the islands of Santiago, Bartolomé, Pinzón, Rábida, and very likely nearby islets in the Galápagos Islands, Ecuador. The estimated extent of occurrence is 1,164 km2 by minimum convex polygon and the area of occupancy is estimated at 444 km2 . The population size is poorly known and estimated at 450–4,000 total iguanas, with fewer than 2,400 mature individuals. Genetic data indicate a critically low effective population size. Overall population trend is unknown, but is subject to extreme reductions and fluctuations during El Niño events, which are predicted to intensify in the future with ongoing climate change. Invasive Black Rats threaten this iguana more severely when compared to other subspecies, as the islands in its distribution have scarce food resources for rats. Santiago Marine Iguanas are threatened by a region-wide increase in human population and visitation that has multiplied the impacts from stress, marine pollution, habitat degradation, and chance of invasive species introductions and emergent diseases. Land-based tourist presence and intensity has been shown to have a significant overall negative effect on iguana health....