Cucumber Slough is a saltwater stream located within the Mosquito Lagoon system in Brevard County, Florida. It is part of the larger Indian River Lagoon estuary, characterized by brackish to salt water. The slough is situated approximately 6.6 kilometers from the main body of Mosquito Lagoon, placing it in a sheltered backcountry area. The primary access point is the Bio Lab boat ramp, located within the Merritt Island National Wildlife Refuge. This ramp provides direct entry to the lagoon system from which Cucumber Slough can be reached. The Haulover Canal area is very busy on weekends, making the Bio Lab ramp a potentially quieter launch site. The paddling environment is a coastal marsh and shallow water system. The area is known for its wildlife, including species like red drum. As a tidal feature connected to Mosquito Lagoon and the Indian River Lagoon, paddlers must plan for tidal currents. The water flow in the slough and connecting channels will be influenced by the tides, so consulting a tide chart for the Mosquito Lagoon area is essential for timing a trip to paddle with or against the current. Wind exposure can be significant over the open waters of the adjacent Mosquito Lagoon before reaching the slough, so checking wind forecasts is advised. The region is part of a national wildlife refuge, so paddlers should be aware of and comply with all applicable federal and state regulations, including any specific rules for the refuge waters.