### structure | barrier:

Jetty
* Jetties also can serve as spawning habitat for walleyes.
* Jetties are rigid shore protection structures that extend from the beach into the surf zone
  - wharfs

Language barrier
* are a major issue in international organization information
  - problem for both parents and teachers
  - barriers
* can also cause frustration in hospital settings
  - pose problems when parents rely on their children for interpretation
* prevent refugees from getting the services to which they are entitled.

Moisture barrier
* keep hair from curling up or frizzing out even on the longest high humity days.
* prevent excess rain or puddles from sluicing conditioning oils out of leather.

Natural barrier
* mark boundaries.
* prevent movement.

Physical barrier
* Most physical barriers are made of metal.
* are also effective in reducing traffic volume
  - common examples of indirect discrimination
  - effective at preventing larvae from entering a field
  - important in termite, house fly, and rodent control
  - often the most imposing barriers to diffusion
* are the first line of defense against infection
  - use of artificial material, for example, netting over fruits
* have effects
  - significant effects

Psychological barrier
* are far more common in running than physical barriers.
* exist when people think the shoreline is unsafe or inaccessible.

Radiant barrier
* Some radiant barriers have a reflective surface on both sides.
* are sheets of aluminum foil laminated to paper.
* can also reduce indoor heat losses through the ceiling in the winter.

### structure | barrier:

Rail
* Some rails have plumages
  - spectacular plumages
* allows hundreds of tracks with thousands of trains to cross the continent.
* are a blight on society
  - any edge of the boat at or above the waterline
  - bars
  - birds
* are located in race tracks
  - subways
  - train stations
  - railways
* build some of their nests on the rafts' tangly brush.
* can reach nearly every urban area in the world.
* exhibit very little sexual dimorphism in either plumage or size.
* fiercely defend their breeding territories against other rails.
* have dark plumage, a short neck and wings, and long legs.
* includes bases
  - sections
* is by far the most common means of transporting goods to Siberia
  - energy efficient and friendly to the environment
  - fast transit
  - high-capacity transit
  - streetcar girder rail with concrete paving
* is the dominant mode of transportation
  - quickest way to travel between the main urban centers
  - smart way to save time and money
  - used for East to West coast deliveries for bulk items, such as rubber mulch
* live in the marshes year round and appear to be relatively sedentary.
* means the horizontal member of a window or door.
* pays property tax on every foot of land on which it operates.
* plays an important role in making cities liveable.
* remains the safest form of surface transport.

### structure | barrier | rail:

Clapper rail
* build nests low in the marsh, near tidal sloughs.
* feed on crayfish, small fish, clams, isopods, and a variety of insects.

Corncrake
* are long distance migrants and spend the winter in the savanna of East Africa.
* hide in the grasses.

Guardrail
* are a natural rusted brown to blend with the earth and trees
  - safety requirements on most bridges
* keep people and wheels safely on the ramp at all times.

Hand rail
* Most hand rails have a support function along stairways.
* are located in subways.

Heavy rail
* can be one of the most nicest forms of public transit.
* is an electric railway with the capacity for a heavy volume of traffic.

King rail
* are North America's largest true rails.
* have specific water depth needs for breeding and feeding.
* leave Missouri during the fall, heading south to warmer wintering areas.