Home/Ecosystems/ Southeast Florida Coastal Hammock

Southeast Florida Coastal Hammock

EVT 7337Southeast Florida Maritime Hammock

CES411.369GNRTreeHardwood

Summary

This ecological system occurs as a narrow band of hardwood forest and shrublands along the Atlantic Coast of southeastern Florida (approximately Volusia County southward). It is found on stabilized, old, coastal dunes, often with substantial shell components. The vegetation is characterized by hardwood species with tropical affinities, such as Guapira discolor and Exothea paniculata. As such, the northern extent of this type is limited by periodic freezes. This system is closely related to both inland tropical hammocks and southwest Florida maritime hammocks, and may share some species overlap with each.

Source: NatureServe Explorer

Environment

This system occurs along the coast on stabilized, old coastal dunes, often with substantial shell components. The northern extent of this type is limited by periodic freezes.

Source: NatureServe Explorer

Dynamics

The northern extent of this type is limited by periodic freezes and lack of cold tolerance of tropical plants, such as Guapira discolor and Exothea paniculata (Johnson and Muller 1993a). Maritime hammocks are relatively stable forest communities, as long as the canopy remains intact and the underlying landform is stable (FNAI 1990). Surface fires may help to maintain the open understory (Landfire 2007a). The shrub-dominated, coastal strand communities are considered ecotonal, and historically burned more frequently than maritime hammocks, possibly every 4-5 years (Austin and Coleman-Marois 1977). However, there is some disagreement on this point. There is little information on natural fire frequency in coastal strand (FNAI 2010a). The low stature of strand is due to the influence of storms and the ongoing salt spray pruning (FNAI 2010a). Fire is not needed to explain the shrub-dominated vegetation of coastal strands (Landfire 2007a).

Source: NatureServe Explorer

Threats

Coastal development has been and remains a big threat to this vegetation. Fragmentation of remaining areas is also a threat. Invasion by exotic plants, such as Casuarina equisetifolia, Colubrina asiatica, Cupaniopsis anacardioides, Neyraudia reynaudiana, Scaevola sericea var. taccada (= Scaevola taccada), and Schinus terebinthifolius following natural disturbance (such as hurricanes) is an ongoing threat (Johnson 1994b, FNAI 2010a). Casuarina equisetifolia is the biggest invasive exotic plant threat. Due to its competitive abilities, Casuarina equisetifolia can completely replace the native plant species in recolonizing coastal strand after storms or as beaches build out after natural coastal disturbances (Johnson 1994b). Persea borbonia in coastal strand communities has been affected by laurel wilt disease, which is caused by a fungus (Raffaelea lauricola) spread by an exotic wood-boring beetle (Xyleborus glabratus) and is fatal to Persea borbonia shrubs over 2.5-cm dbh (FNAI 2010a).

Source: NatureServe Explorer

Distribution

Endemic to south Florida.

Source: NatureServe Explorer

Ecologically Associated Plant Species

Plant species that characterize this ecosystem type, organized by vegetation stratum. These are species ecologically associated with the ecosystem, not confirmed present in any specific area.

Tree canopy

Quercus virginiana

Shrub/sapling (tall & short)

Coccoloba uvifera, Exothea paniculata, Guapira discolor, Myrcianthes fragrans, Pithecellobium keyense, Psychotria nervosa, Quercus geminata, Serenoa repens, Sideroxylon tenax

Nonvascular

Acroporium smallii, Plagiochila micropteryx

Source: NatureServe Ecological System assessment

Ecologically Associated Animals (2)

Animal species ecologically associated with this ecosystem type based on NatureServe assessment. These are species whose habitat requirements overlap with this ecosystem, not confirmed present in any specific roadless area.

Reptiles (2)

Common Name	Scientific Name	G-Rank
Green Anole	Anolis carolinensis	G5
Brown Watersnake	Nerodia taxispilota	G5

Source: NatureServe Ecological System assessment

At-Risk Species Associated with this Ecosystem (3)

Species with conservation concern that are ecologically associated with this ecosystem type. G-Rank indicates global conservation status: G1 (critically imperiled) through G5 (secure). ESA status indicates U.S. Endangered Species Act listing.

Common Name	Scientific Name	G-Rank	ESA Status
Small's Acroporium Moss	Acroporium smallii	G1?	--
a liverwort	Plagiochila micropteryx	G2?	--
Tough Bumelia	Sideroxylon tenax	G3?	--

Source: NatureServe Ecological System assessment

Component Associations (6)

Plant community associations that occur within this ecological system. Associations are the finest level of the U.S. National Vegetation Classification (USNVC) and describe specific, repeating assemblages of plant species. Each association represents a distinct community type that may be found where this ecosystem occurs.

Name	G-Rank
Ficus aurea - Sideroxylon foetidissimum - Bursera simaruba / Eugenia foetida - Guapira discolor Forest	G1	NatureServe
Quercus geminata - Quercus myrtifolia - Serenoa repens - Sideroxylon tenax - Ximenia americana Scrub	G1	NatureServe
Quercus virginiana - Sabal palmetto - Persea borbonia / Myrcianthes fragrans Forest	G1	NatureServe
Scaevola plumieri - Coccoloba uvifera / Uniola paniculata Shrubland	G1	NatureServe
Serenoa repens - Coccoloba uvifera - Pithecellobium keyense - Dalbergia ecastaphyllum Scrub	G1	NatureServe
Serenoa repens - Coccoloba uvifera - Sideroxylon tenax - Myrcianthes fragrans - Myrsine cubana Scrub	G2	NatureServe

State Conservation Ranks (1)

Subnational conservation status ranks (S-ranks) assigned by Natural Heritage Programs in each state where this ecosystem occurs. S1 indicates critically imperiled at the state level, S2 imperiled, S3 vulnerable, S4 apparently secure, and S5 secure. An ecosystem may be globally secure but imperiled in specific states at the edge of its range.

State	S-Rank
FL	SNR

Methodology and Data Sources

Ecosystem classification: Ecosystems are classified using the LANDFIRE 2024 Existing Vegetation Type (EVT) layer, mapped to NatureServe Terrestrial Ecological Systems via a curated crosswalk. Each EVT is linked to the USNVC (U.S. National Vegetation Classification) hierarchy through pixel-level co-occurrence analysis of LANDFIRE EVT and NatureServe IVC Group rasters across all roadless areas.

Vegetation coverage: Coverage percentages and hectares are derived from zonal statistics of the LANDFIRE 2024 EVT raster intersected with roadless area boundaries.

Ecosystem narratives and community species: Sourced from the NatureServe Explorer API, representing professional ecological assessments of vegetation composition, environmental setting, dynamics, threats, and characteristic species assemblages.

IVC hierarchy: The International Vegetation Classification hierarchy is sourced from the USNVC v3.0 Catalog, providing the full classification from Biome through Association levels.

Component associations: Plant community associations listed as components of each NatureServe Ecological System. Association data from the NatureServe Explorer API.

State ranks: Conservation status ranks assigned by NatureServe member programs in each state where the ecosystem occurs.