Reproduction: The Keys tree cactus flowers year round, peaking in July, August and September. Flowers bloom (and smell garlicky) at night (Hennessey and Habeck 1994). Seed viability was 57.7% (N=6397) and fruit set was 21.9% (N=32) in laboratory trials (Adams, undated report). Natural History: Information on population age class, growth rates, and architecture is contained in Adams and Lima (1994). Dr. Peter Stiling, of the University of South Florida, may be continuing natural history research. Predation: Adams and Lima (1994) noted ants and cardinals predating on the seeds and fruit, respectively. Hennessey, M. K. and D. H. Habeck (1994). ""Observations on reproduction of an endangered cactus, Cereus robinii (Lemaire) L. Benson."" Florida Scientist 57: 93-101. This rare cactus is subjected to mosquito insecticide spraying which has an unknown effect on its pollinators. No pollinators were observed, so cross pollination by animals remains unconfirmed. Its floral biology strongly suggests pollination by bats or moths. Pesticide spraying could have impacts on its reproductive cycle.

Known from the Florida Keys and Cuba and rare throughout its range, with only 7 occurrences believed extant in the United States. Since the mid-1990s, significant declines have been observed at the Florida Keys sites. The species is subject to cactus collection and its limited habitat is disappearing rapidly due to encroaching development and agricultural conversion; only a few of the occurrences are formally protected. It is also threatened by increasing soil salinity due to sea level rise and storm surge; hurricanes are also occassionally destructive to the few populations. Sea level and storm impacts are predicted to worsen as climate change proceeds, especially given that there is limited connectivity between this species' habitat and higher ground.

Known threats include habitat destruction and hurricanes (the latter of which limit size, but probably not reproduction) (USFWS 1986). Other possible threats include canopy closure, salt water intrusion, drainage, competition, and accumulation of soil

Populations: 9 in Florida (FNAI 1998), 1 unconfirmed in Cuba (Adams, undated report) Individuals: 624 in the Keys (Adams and Lima 1994), and an unknown number in Cuba

Reproduction: The Keys tree cactus flowers year round, peaking in July, August and September. Flowers bloom (and smell garlicky) at night (Hennessey and Habeck 1994). Seed viability was 57.7% (N=6397) and fruit set was 21.9% (N=32) in laboratory trials (Adams, undated report). Natural History: Information on population age class, growth rates, and architecture is contained in Adams and Lima (1994). Dr. Peter Stiling, of the University of South Florida, may be continuing natural history research. Predation: Adams and Lima (1994) noted ants and cardinals predating on the seeds and fruit, respectively. Hennessey, M. K. and D. H. Habeck (1994). ""Observations on reproduction of an endangered cactus, Cereus robinii (Lemaire) L. Benson."" Florida Scientist 57: 93-101. This rare cactus is subjected to mosquito insecticide spraying which has an unknown effect on its pollinators. No pollinators were observed, so cross pollination by animals remains unconfirmed. Its floral biology strongly suggests pollination by bats or moths. Pesticide spraying could have impacts on its reproductive cycle.

Responsible Agencies: Florida Department of Environmental Protection, Florida Keys National Wildlife Refuge, U.S. Fish and Wildlife Service, private landowners. The National Wildlife Refuge and USFWS protect the land containing the largest population of the Keys tree cactus, but they do not regularly monitor the population. FDEP conducts periodic monitoring of the populations on its lands.

A regular monitoring schedule on Federal lands. A clear summary of the status of the Keys tree cactus on private lands. Outplanting of the cactus onto sites where it currently or historically is/was found. Research on the effects of light levels, salt water, organic matter or competition.

It has not been determined with certainty whether the two apparent forms of the Keys tree cactus are genetically nondistinct. If an outplanting were to take place, seeds need to be collected and used to propagate seedlings for outplanting.