Alternative Text Description for Key Silverside (Threatened) Distribution Map

TABLE OF CONTENTS

MAP OVERVIEW

This map displays the geographic distribution of the Key Silverside, a threatened species in Florida, showing where this species occurs across the Florida Keys and surrounding coastal waters. The map uses hatched polygons to indicate areas where Key Silverside populations are documented, representing their range as part of Florida's official endangered and threatened species list. The visualization focuses on the marine and coastal habitat areas where this imperiled species is found.

GEOGRAPHIC CONTEXT

The map covers the Florida Keys archipelago and adjacent waters, extending from Key West in the southwest to the upper keys near Key Largo in the northeast. Several labeled locations provide geographic reference points including Key West at the southwestern end, Great White Heron National Wildlife Refuge in the lower keys, Cudjon Key and Big Pine Key in the middle keys, Duck Key in the mid-to-upper keys, and Key Largo at the northeastern extent. The map also shows Monroe County labeled in the upper portion, and a small portion of mainland Florida appears in the upper right corner. The water body shown is part of the Gulf of America to the north and west of the keys, with the Atlantic Ocean to the south and east.

KEY INSIGHTS

The Key Silverside's distribution follows a distinctive linear pattern along the entire Florida Keys chain, with the habitat areas concentrated in the nearshore and shallow water environments surrounding the islands. The mapped range shows nearly continuous coverage along both the northern (Gulf of America-facing) and southern (Atlantic-facing) sides of the keys, suggesting this species utilizes coastal waters throughout the archipelago. Notable concentrations of habitat appear around the lower and middle keys, particularly in areas surrounding Great White Heron National Wildlife Refuge, Big Pine Key, and the waters between major islands. The distribution extends as a narrow coastal band rather than occupying large offshore areas, indicating the species' association with shallow, near-island marine environments.

VISUAL ELEMENTS

Key Silverside (Threatened) Distribution

This layer represents the documented range and habitat areas for the Key Silverside threatened species throughout the Florida Keys region.

Threatened Species Habitat Areas (purple crosshatch pattern)

Appearance:

The habitat areas are shown as purple or magenta crosshatched polygons overlaid on the light blue water background. The crosshatch pattern consists of diagonal lines creating a mesh or grid appearance.

Distribution:

The habitat areas form an almost continuous band along the entire Florida Keys chain, wrapping around individual islands and keys from Key West in the southwest through the middle keys to Key Largo in the northeast.

Notable locations:

Significant habitat areas surround Key West and the lower keys near Great White Heron National Wildlife Refuge, extend through the middle keys around Cudjon Key and Big Pine Key, and continue through the upper keys to Duck Key and Key Largo. The mapped areas appear as irregular polygons that follow the shoreline contours and encompass shallow water zones.

Spatial patterns:

The distribution shows a linear, archipelago-following pattern with habitat areas forming circular or oval buffers around individual islands and keys. The pattern suggests nearshore coastal dependency, with the habitat zones extending outward from the islands into adjacent waters but not extending far offshore. Some areas show wider habitat zones where multiple keys are clustered together, while narrower bands occur along more isolated stretches of the island chain.

Overlapping Patterns

The threatened species habitat areas overlap with the locations of several named keys and the Great White Heron National Wildlife Refuge, indicating that Key Silverside populations occupy waters adjacent to both developed areas (such as Key West and Key Largo) and protected natural areas.

SYMBOL GUIDE

ADDITIONAL INFORMATION

This map represents a single thematic layer extracted from Florida's State Imperiled Species dataset, specifically filtered to show only the Key Silverside distribution. The Key Silverside is designated as a threatened species under Florida's official endangered and threatened species list. The mapped areas represent the species' known range as documented in the Imperiled Species Management Plan (ISMP) and Species Action Plan (SAP), with data updated in December 2025. Users should note that the habitat boundaries shown represent documented distribution areas and may reflect both current populations and historically occupied habitats within the species' range.

DATA CONTEXT

Data Source:

The data comes from Florida's official endangered and threatened species list, with range and distribution information depicted in the state's Imperiled Species Management Plan (ISMP) and Species Action Plan (SAP) of 2013, with updates completed in December 2025. Data source layer name: STATE_IMPERILED_SPECIES_DEC25.

Definition Query:

The map displays a filtered subset of the state imperiled species dataset, showing only records where COMMON_NAME='KEY SILVERSIDE', limiting the view to this single threatened species rather than displaying all imperiled species in the dataset.

Scale Information:

The map shows a regional scale view appropriate for displaying the entire Florida Keys archipelago and the full extent of the Key Silverside's documented range across this geographic area.

Coordinate System:

NAD_1983_HARN_Florida_GDL_Albers (WKID 3087)

Time Period of Content:

The dataset was updated in December 2025, reflecting the most current information on Key Silverside distribution as of that date, based on species management plans originally established in 2013.

Limitations:

The mapped areas represent documented range and distribution based on available survey data and species management plans. Actual species presence may vary within the mapped zones, and the boundaries represent general habitat areas rather than precise population locations. Some areas may reflect historical range rather than current verified populations.

Map Coverage:

The map covers the entire Florida Keys from Key West in the southwest to Key Largo in the northeast, including adjacent coastal waters in Monroe County. A small portion of mainland Florida is visible in the upper right corner for geographic context.

The alternative text description of this map was AI-generated and may contain inaccuracies.