Find the meaning of outdoor words you need to know in the DTO.com Glossary—you’ll find definitions of words that relate specifically to the biology, management, products, equipment and related activities for all of DTO’s portals on hunting, fishing, shooting sports and more.

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s
Rate of change (as of January 1, 1900) in mean longitude of Moon. s = 0.549,016,53

S1
Solar diurnal constituent. Speed = T = 15.000,000,0

S2
Principal solar semi diurnal constituent. This constituent represents the rotation of the Earth with respect to the Sun. Speed = 2T = 30.000,000,0

S4, S6
Shallow water overtides of the principal solar constituent. Speed of S4 = 2S2 = 4T = 60.000,000,0

Sa
Solar annual constituent. This constituent, with Ssa, accounts for the nonuniform changes in the Sun's declination and distance. In actuality, they mostly reflect yearly meteorological variations influencing sea level. Speed = h = 0.041,068,64

sacrifice area/site
In range management, a site allowed to be overgrazed to obtain efficient overall use of the management area. In cultural resource management, it may refer to a site intentionally sacrificed to extensive public use in order to preserve the larger cultural area.

salient
Coastal formation of beach material developed by wave refraction and diffraction and longshore drift comprising of a bulge in the coastline towards an offshore island or breakwater, but not connected to it as in the case of a tombolo. See also ness, cusp.

salinity (S)
The total amount of solid material in grams contained in 1 kilogram of sea water when all the carbonate has been converted to oxide, the bromine and iodine replaced by chlorine, and all organic matter completely oxidized. S(

salinity gradient
Change in salinity with DEPTH, expressed in parts per thousand per foot.

salt-wedge estuary
In this circulation type, the density-driven component dominates and two well-mixed layers are separated by a sharp halocline. The seawater entering the channel appears as a tongue or wedge.

saltation
A term used to describe the movement of a particle being transported by wind or water which is too heavy to remain in suspension. The particle is rolled forward by the current, generates lift and rises, loses the forward momentum supplying the lift and settles to the floor, where the process is repeated. The size of the particles which can be saltated depends upon the velocity of the current and its density, e.g., water will saltate larger particles than air at the same velocity.

sand
An unconsolidated (geologically) mixture of inorganic soil (that may include disintegrated shells and coral) consisting of small but easily distinguishable grains ranging in size from about .062 mm to 2.0 mm.

sand bar
(1) See BAR. (2) In a river, a ridge of sand built to or near the surface by river currents.

sand dune
A dune formed of sand.

sand spit
A narrow sand embankment, created by an excess of deposition at its seaward terminus, with its distal end (the end away from the point of origin) terminating in open water.

sand waves
(1) Longshore sand waves are large-scale features that maintain form while migrating along the shore with speeds on the order of kilometers per year. (2) Large-scale asymmetrical bedforms in sandy river beds having high length to height ratios and continuous crestlines.

sanitation salvage
The removal of dead, damaged or susceptible trees primarily to prevent the spread of pests or disease and promote forest health.

sapling
A loose term for a young tree more than a few feet tall and an inch or so in diameter that is typically growing vigorously.

Sargasso Sea
The west central region of the subtropical gyre of the North Atlantic Ocean. It is bounded by the North Atlantic, Canary, North Equatorial, and Antilles Currents, and the Gulf Stream. It is characterized by the absence of any well-marked currents and by large quantities of drifting Sargassum, or gulf weed.

saros
: A period of 223 synodic months corresponding approximately to 19 eclipse years or 18.03 Julian years, and is a cycle in which solar and lunar eclipses repeat themselves under approximately the same conditions.

sawtimber
Trees that are 9 inches in diameter at breast height or larger that can be made into lumber.

scale
In ecosystem management, it refers to the degree of resolution at which ecosystems are observed and measured.

scapluars
Area of feathers between the back and the wings.

scarp
see escarpment.

scavenger species
birds that often or habitually feed on dead, sick, or injured prey. Includes crows, vultures, bald eagles, and gulls.

scoping
The ongoing process to determine public opinion, receive comments and suggestions, and determine issues during the environmental analysis process. It may involve public meetings, telephone conversations, or letters.

scour protection
Protection against erosion of the seabed in front of the toe.

sea
(1) See ocean. (2) A large body of salt water, second in rank to an ocean, more or less landlocked and generally part of, or connected with, an ocean or a larger sea. (3) Waves caused by wind at the place and time of observation. (4) State of the ocean or lake surface, in regard to waves.

sea breeze
A breeze that blows from the sea toward the land caused by unequal heating of land and water masses.

sea cliff
A cliff situated at the seaward edge of the coast.

sea defenses
Works to prevent or alleviate flooding by the sea.

sea defenses
Works to prevent or alleviate flooding by the sea.

sea ducks
ducks that frequent open ocean, even though some species are often found on coastal bays, larger inland lakes, and in other inland waters. Species include oldsquaw, eiders, scoters, and harlequin duck.

sea grass
Members of marine seed plants that grow chiefly on sand or sand-mud bottom. They are most abundant in water less than 9 m deep. The common types are: Eel grass (Zostera), Turtle grass (Thallasia) and Manatee grass (Syringodium).

sea level datum (SLD)
: An obsolete term. See National Geodetic Vertical Datum of 1929 and mean sea level.

sea level rise
The long-term trend in mean sea level.

sea puss
A dangerous longshore current; a rip current caused by return flow; loosely, the submerged channel or inlet through a bar caused by those currents.

seacoast
The coast adjacent to the sea or ocean.

seacoast
The coast adjacent to the sea or ocean.

seam lines
Are where the faster water meets with the slower water, are usually a good spot to find fish. The fish rest in slower water and move into the faster water to escape predators or catch food

seamount
Conical mountain rising 1000 m or more above the sea floor. Seashore: (1) (Law) All ground between the ordinary high-water and low-water mark. (2) The shore of the sea or ocean.

seawall
(1) A structure built along a portion of a coast primarily to prevent erosion and other damage by wave action. It retains earth against its shoreward face. (2) (SMP) A structure separating land and water areas primarily to prevent erosion and other damage by wave action. Generally more massive and capable of resisting greater wave forces than a bulkhead.

Sechhi disk
Visibility disk used to measure the transparency of the water column. Sediment: (1) Loose, fragments of rocks, minerals or organic material which are transported from their source for varying distances and deposited by air, wind, ice and water. Other sediments are precipitated from the overlying water or form chemically, in place. Sediment includes all the unconsolidated materials on the sea floor. (2) (SMP) The fine grained material deposited by water or wind.

second growth
Forest growth that was established after some kind of interference with the previous forest crop, such as cutting, fire, or insect attack.

second reduction
same as phase reduction

secondaries
Flight feathers attached to the "elbow".

secondary control tide station
A tide station at which continuous observations have been made over a minimum period of 1 year but less than 19 years. The series is reduced by comparison with simultaneous observations from a primary control tide station. This station provides for a 365-day harmonic analysis including the seasonal fluctuation of sea level. See tide station, primary control tide station, tertiary tide station, and subordinate tide station (1).

secondary coverts
Feathers protecting and covering the secondaries.

secular trend
See apparent secular trend as preferred term.

sediment cell
In the context of a strategic approach to coastal managment, a length of coastline in which interruptions to the movement of sand or shingle along the beaches or nearshore sea bed do not significantly affect beaches in the adjacent lengths of coastline. See littoral cell.

sediment sink
A point or area at which beach material is irretrievably lost from a coastal cell, such as an estuary, or a deep channel in the seabed.

sediment source
A point or area on a coast from which beach material arises, such as an eroding cliff, or river mouth.

sediment transport
The main agencies by which sedimentary materials are moved are: gravity (gravity transport); running water (rivers and streams); ice (glaciers); wind; the sea (currents and longshore drift). Running water and wind are the most widespread transporting agents. In both cases, three mechanisms operate, although the particle size of the transported material involved is very different, owing to the differences in density and viscosity of air and water. The three processes are: rolling or traction, in which the particle moves along the bed but is too heavy to be lifted from it; saltation; and suspension, in which particles remain permanently above the bed, sustained there by the turbulent flow of the air or water.

sediment transport paths
The routes along which net sediment movement occurs.

seed tree harvest
Removal of the mature timber crop from an area in one cut, except for a certain number of seed bearers.

seiche
A stationary wave usually caused by strong winds and/or changes in barometric pressure. It is found in lakes, semi enclosed bodies of water, and in areas of the open ocean. The period of a seiche in an enclosed rectangular body of water is usually represented by the formula: Period (T) = 2L / square root(gd) in which L is the length, d the average depth of the body of water, and g the acceleration of gravity. See standing wave.

seine nets
A large net with sinkers on one edge and floats on the other that hangs vertically in the water and is used to enclose fish when its ends are pulled together or are drawn ashore; used by Native American fishers.

seismic reflection
The return of part of the energy of seismic waves to the earth’s surface after the waves bounce off a rock boundary.

seismic refraction
The bending of seismic waves as they pass from one material to another.

seismic sea wave
Same as tsunami.

seismic waves
A long-period wave caused by an underwater seismic disturbance or volcanic eruption.

semidiurnal
Having a period or cycle of approximately one-half of a tidal day. The predominant type of tide throughout the world is semi diurnal, with two high waters and two low waters each tidal day. The tidal current is said to be semi diurnal when there are two flood and two ebb periods each day. A semi diurnal constituent has two maxima and two minima each constituent day, and its symbol is the subscript 2. See type of tide.

semidiurnal tide
Tides occurring twice daily. There are two high and two lows per tidal day.

sensing, remote
The response of an instrument or organism to stimuli from a distant source.

sensitive species
Plant or animal species which are susceptible to habitat changes or impacts from activities. The official designation is made by the USDA Forest Service at the Regional level and is not part of the designation of Threatened or Endangered Species made by the US Fish and Wildlife Service.

sequence of current
The order of occurrence of the four tidal current strengths of a day, with special reference as to whether the greater flood immediately precedes or follows the greater ebb.

sequence of tide
The order in which the four tides of a day occur, with special reference as to whether the higher high water immediately precedes or follows the lower low water.

seral
The stage of succession of a plant or animal community that is transitional. If left alone, the seral stage will give way to another plant or animal community that represents a further stage of succession.

set (of current)
The direction towards which the current flows.

setback
(SMP) A required open space, specified in shoreline master programs, measured horizontally upland from an perpendicualr to the ordinary high water mark.

sex ratio
the proportion of males to females in a population.

shadows
Shadows in the water indicate where the water is deeper. As your eyes adjust, you should be able to distinguish the shadows of the fish. This tells you where to cast your line

shallow water
Water of such depth that surface waves are noticeably affected by bottom topography. Typically this implies a water depth equivalent to less than half the wave length.

shallow water constituent
A short-period harmonic term introduced into the formula of tidal (or tidal current) constituents to take account of the change in the form of a tide wave resulting from shallow water conditions. Shallow water constituents include the overtides and compound tides.

shallow water wave
A wave is classified as a shallow water wave whenever the ratio of the depth (the vertical distance of the still water level from the bottom) to the wave length (the horizontal distance between crests) is less than 0.04. Such waves propagate according to the formula: C = square root(gd) where C is the wave speed, g the acceleration of gravity, and d the depth. Tidal waves are shallow water waves.

shallow water wave
A progressive gravity wave which is in water less than 1/25 the wave length in DEPTH.

shank
The straight part of a hook.

shear
A quasi-horizontal layer moving at a different velocity relative to the layer directly below and/or above.

sheet erosion
The removal of a thin layer of surface material, usually topsoil, by a flowing sheet of water.

sheet flow
Sediment grains under high sheer stress moving as a layer that extends from the bed surface to some distance below (on the order of a few cm). Grains are transported in the direction of fluid flow. Sheet, smooth: A sheet on which field control and hydrographic data such as soundings, depth curves, and regions surveyed with a wire drag are finally plotted before being used in making a final chart.

shelf, continental
See continental shelf.

shelterbelts
human-made habitats created by planting shrubs and trees in rows to protect homesteads and fields from wind.

shelterwood
A cutting method used in a more or less mature stand, designed to establish a new crop under the protection of the old.

shingle
A loose term for coarse beach material, a mixture of GRAVEL, pebbles and larger material, often well-rounded and of hard rock, e.g. chert, flint etc.

shoal
(1) (noun) A detached area of any material except rock or coral. The depths over it are a danger to surface navigation. Similar continental or insular shelf features of greater depths are usually termed banks. (2) (verb) To become shallow gradually. (3) To cause to become shallow. (4) To proceed from a greater to a lesser depth of water.

shore
That strip of ground bordering any body of water which is alternately exposed, or covered by tides and/or waves. A shore of unconsolidated material is usually called a beach.

shore terrace
A terrace made along a coast by the action of waves and shore currents; it may become land by the uplifting of the shore or the lowering of the water.

shorebirds
birds that feed at the edge of shallow water, along mudflats, and in shallow wetlands where water depths do not exceed a few inches. Typically these birds feed on invertebrates and include such species as American avocet, black-necked stilt, curlews, plovers, phalaropes, sandpipers, yellowlegs, and sanderling.

shoreface
The narrow zone seaward from the low tide shoreline permanently covered by water, over which the beach sands and gravels actively oscillate with changing wave conditions.

shoreline (coastline)
The intersection of the land with the water surface. The shoreline shown on charts represents the line of contact between the land and a selected water elevation. In areas affected by tidal fluctuations, this line of contact is the mean high water line. In confined coastal waters of diminished tidal influence, the mean water level line may be used. See coast line.

shoreline management
The development of strategic, long-term and sustainable COASTAL DEFENSE and land-use policy within a sediment cell.

short-crested wave
A wave, the crest length of which is of the same order of magnitude as the wave length. A system of short-crested waves has the appearance of hills being separated by troughs.

shoulder
Feathers overlying bases of median secondary coverts. Synonym(s): lesser secondary coverts, marginal coverts. In picture it is referred to as lesser secondary coverts.

side
Area between the belly and the wing.

side of neck
Area of neck between foreneck and hindneck.

sidereal day
The time of the rotation of the Earth with respect to the vernal equinox. It equals approximately 0.997,27 of a mean solar day. Because of the precession of the equinoxes, the sideral day thus defined is slightly less than the period of rotation with respect to the fixed stars, but the difference is less than the hundredth part of a second.

sidereal month
Average period of the revolution of the Moon around the Earth with respect to a fixed star, equal to 27.321,661 mean solar days.

sidereal time
This is usually defined by astronomers as the hour angle of the vernal equinox. The sidereal day is the interval between two successive upper transits of the vernal equinox. It is to be noted that when applied to the month and year the word sidereal has reference to motion with respect to the fixed stars, while the word tropical is used for motion with respect to the vernal equinox. Because of the precession of the equinox there is a slight difference.

sidereal year
Average period of the revolution of the Earth around the Sun with respect to a fixed star. Its length is approximately 365.256,4 mean solar days.

sigma-t
an expression of density as a function of temperature and salinity (at atmospheric pressure) in a convenient numerical form. See density.

sigma-zero
An expression of density as a function of salinity (at atmospheric pressure and 0

significant wave
A statistical term relating to the one-third highest waves of a given wave group and defined by the average of their heights and periods.

significant wave period
Average period of the highest one-third of the waves for a stated interval of time.

silt
sediment particles with a grain size between 0.004 mm and 0.062 mm, i.e. coarser than clay particles but finer than sand.

silvicultural system
The cultivation of forests; the result is a forest of a distinct form. Silvicultural systems are classified according to harvest and regeneration methods and the type of forest that results.

silvicultural treatment
results in small openings that form mosaics of age class groups in the forest.

silviculture
The art and science that promotes the growth of single trees and the forest as a biological unit.

single action
A reel where the handle is attached directly to the spool, without the aid of gears.

single tree selection
See individual tree selection.

site preparation
The general term for removing unwanted vegetation, slash, roots, and stones from a site before reforestation. Naturally occurring wildfire, as well as prescribed fire can prepare a site for natural regeneration.

size class
One of the three intervals of tree stem diameters used to classify timber in the Forest Plan data base. The size classes are: Seedling/Sapling (less than 5 inches in diameter); Pole Timber (5 to 7 inches in diameter); Sawtimber (greater than 7 inches in diameter)

skidding
Hauling logs by sliding, not on wheels, from stump to a collection point.

skirted spool
A spool that allows for greater line capacity, longer casts and fewer tangles, while better protecting the reel's internal components from salt and moisture.

skyline logging
A logging system used to remove timber from steep slopes. Logs are brought up-slope on a suspended cable, or skyline. Since the weight of the log is completely or partially supported by the cable, there is little disturbance to soil or other vegetation.

slack water (slack)
The state of a tidal current when its speed is near zero, especially the moment when a reversing current changes direction and its speed is zero. The term also is applied to the entire period of low speed near the time of turning of the current when it is too weak to be of any practical importance in navigation. The relation of the time of slack water to the tidal phases varies in different localities. For a perfect standing tidal wave, slack water occurs at the time of high and of low water, while for a perfect progressive tidal wave, slack water occurs midway between high and low water. See slack; ebb begins and slack; flood begins.

slack; ebb begins (slack before ebb)
The slack water immediately preceding the ebb current.

slack; flood begins (sack before flood)
The slack water immediately preceding the flood current.

slash
The residue left on the ground after timber cutting or left after a storm, fire, or other event. Slash includes unused logs, uprooted stumps, broken or uprooted stems, branches, bark, etc.

slide
In mass wasting, movement of a descending mass along a plane approximately parallel to the slope of the surface. Slip face: The steep, downwind slope of a dune; formed from loose, cascading sand that generally keeps the slope at the angle of repose (about 34 degrees). Slope: The degree of inclination to the horizontal. Usually expressed as a ratio, such as 1:25, indicating one unit rise in 25 units of horizontal distance; or in a decimal fraction (0.04). Also called gradient.

slip sinker
A lead weight with a hole through the center that slides freely up and down fishing line unless altered by a swivel or a split shot

slough
A small muddy marshland or tidal waterway which usually connects other tidal areas.

slump
A landslide where the underlying rock masses tilt back as they slide from a cliff or escarpment.

slump
In mass wasting, movement along a curved surface in which the upper part moves vertically downward while the lower part moves outward. Small diurnal range: Difference in height between mean lower low water(MLLW) and mean higher high water (MHHW). Applicable only when the type of tide is either semidinural or mixed.

small diurnal range (Sl)
Difference in height between mean lower high water and mean higher low water.

small game
Birds and small animals normally hunted or trapped.

small tropic range (Sc)
Difference in height between tropic lower high water and tropic higher low water.

snag
A standing dead tree. Snags are important as habitat for a variety of wildlife species and their prey.

soft defenses
Usually refers to beaches (natural or designed) but may also relate to energy-absorbing beach-control structures, including those constructed of rock, where these are used to control or redirect coastal processes rather than opposing or preventing them.

soft plastic bait colors
Solid obviously means one color. Two colors mean that the front part of the bait is one color and the tail part is another color. Laminated means that the top half of the bait is one color and the bottom another.

soil
A layer of weathered, unconsolidated material on top of bed rock; often also defined as containing organic matter and being capable of supporting plant growth. Soil horizons: Layers of soil that are distinguishable by characteristic physical or chemical properties. Solitary wave: A wave consisting of a single elevation (above the water surface) of height not necessarily small compared to the depth, and neither followed or preceded by another elevation or depression of the water surface.

soil compaction
The reduction of soil volume. For instance, the weight of heavy equipment on soils can compact the soil and thereby change it in some ways, such as in its ability to absorb water.

soil productivity
The capacity of a soil to produce a specific crop. Productivity depends on adequate moisture and soil nutrients, as well as favorable climate.

solar day
The period of the rotation of the Earth with respect to the Sun. The mean solar day is the time of the rotation with respect to the mean Sun. The solar day commencing at midnight is called a civil or calendar day, but if the day is reckoned from noon it is known as an astronomical day because of its former use in astronomical calculation.

solar tide
(1) The part of the tide that is due to the tide-producing force of the Sun. (2) The observed tide in areas where the solar tide is dominant. This condition provides for phase repetition at about the same time each solar day.

solar time
Time measured by the hour angle ofthe Sun. It is called apparent time when referred to the actual Sun and mean time when referred to the mean Sun. It is also classified as local, standard, or Greenwich according to whether it is reckoned fromthe local, standard, or Greenwich meridian.

solitary wave
A wave of translation consisting of a single crest rising above the undisturbed water level without any accompanying trough. The rate of advance of a solitary wave depends upon the depth of the water and is usually expressed by the formula: C = Square root(g(d + h)) in which C = rate of advance, g = acceleration of gravity, d = depth of water, and h = height of wave, the depth and height being measured from the undisturbed water level.

Somali (East Africa Coast) Current
An Indian Ocean current setting southwestward along the coast of Somalia. The current reverses and sets to the northeast during the Southwest Monsoon. sorting: Process of selection and separation of sediment grains according to their grain size (or grain shape or specific gravity). Sound: (1) (noun) a relatively long arm of the sea or ocean forming a channel between an island and a mainland or connecting two larger bodies, as a sea and the ocean, or two parts of the same body; usually wider and more extensive than a strait. (2) (verb) To measure the depth of the water.

songbirds
small perching and singing birds that typically belong to the Order Passeriforme, including sparrows, finches, and cardinals.

sorting
Process of selection and separation of sediment grains according to their grain size (or grain shape or specific gravity). Sound: (1) (noun) a relatively long arm of the sea or ocean forming a channel between an island and a mainland or connecting two larger bodies, as a sea and the ocean, or two parts of the same body; usually wider and more extensive than a strait. (2) (verb) To measure the depth of the water.

sound wood
Timber that is in solid, whole, good condition. Sound wood is free from damage, decay, or defects.

sounding
A measured depth of water. On hydrographic charts the soundings are adjusted to a specific plane of reference (sounding datum).

sounding datum
The plane to which SOUNDINGS are referred. See chart datum.

sounding line
A line, wire or cord used in SOUNDING. It is weighted at one end with a plummet.

South Equatorial Current
A current setting westward along and south of the Equator in the Atlantic and Pacific Oceans, and south of the Equator in the Indian Ocean. It occurs immediately south of the Equatorial Counter Current.

Southwest Monsoon Current
Same as Monsoon Current.

special use permit
A permit issued to an individual or group by the USDA Forest Service for use of National Forest land for a special purpose. Examples might be a Boy Scout Jamboree or a mountain bike race.

species
a particular kind of plant or animal. The red fox is on species; the gray fox is a different species.

species of constituent
A classification depending upon the period of a constituent. The principal species are semidiurnal, diurnal, and long-period.

specific volume anomaly, or steric anomaly
The excess in specific volume over the standard specific volume at 35

specific volume, in situ
Volume per unit mass. The reciprocal of density (specific gravity). The specific volume of sea water as a function of salinity, temperature, and pressure. See specific volume anomaly and thermosteric anomaly.

spectacle
eye ring and supraloral line together.

spectra
A very strong, low diameter, braided fishing line.

speculum
Highly colored area on secondaries of several ducks.

speed (of constituent)
The rate f change in the phase of a constituent, usually expressed in degrees per hour. The speed is equal to 360

speed (of current)
The magnitude of velocity. Rate at which the current flows. Usually expressed in knots or centimeters per second.

spincaster
A top-mounted, push-button, closed-face spinning reel

spinners
Spinners are a type of lure consist of a hook and a small, spoon-shaped blade attached to a wire. The blade is designed to spin and thus attract fish as the angler retrieves the lure through the water.

spinning
Fishing by employing an open-face or closed-face spinning reel attached under a spinning rod

spit
(1) A long narrow accumulation of sand or shingle, lying generally in line with the COAST, with one end attached to the land the other projecting into the sea or across the mouth of an estuary. See also ness. (2) (SMP) An accretion shoreform which extends seaward from and parallel to the shoreline.

Spitsbergen Atlantic Current
A current setting northwestward off the southwest coast of Spitsbergen in the Greenland Sea.

spool
The portion of the reel that holds the line.

spool-release button
A mechanism that can engage or disengage the internal gears of a reel.

spotted sunfish
STUMPKNOCKER- Sides are dark with belly usually cream-colored or light red. Peppered with small black spots. Size- Few Stumpknockers approach a pound in weight.

spring creek
A stream that arises from groundwater; usually exhibits nearly constant water volume and temperature all year-round.

spring high water
Same as mean high water springs (MHWS). See spring tides.

spring low water
Same as mean low water springs (MLWS). See spring tides and mean low water springs.

spring range
The average semidiurnal range occurring at the time of spring tides and most conveniently computed from the harmonic constants. It is larger than the mean range where the type of tide is either semidiurnal or mixed, and is of no practical significance where the type of tide is diurnal.

spring tides or tidal currents
Tides of increased range or tidal currents of increased speed occurring semimonthly as the result of the Moon being new or full. The spring range (Sg) of tide is the average range occurring at the time of spring tides and is most conveniently computed from the harmonic constants. It is larger than the mean range where the type of tide is either semi diurnal or mixed, and is of no practical significance where the type of tide is predominantly diurnal. The average height of the high waters of the spring tides is called spring high water or mean high water springs (MHWS) and the average height of the corresponding low waters is called spring low water or mean low water springs (MLWS).

Ssa
Solar semiannual constituent. See Sa. Speed = 2h = 0.082,137,3

stand
A group of trees that occupies a specific area and is similar in species, age, and condition.

stand of tide
Sometimes called a platform tide. An interval at high or low water when there is no sensible change in the height of the tide. The water level is stationary at high and low water for only an instant, but the change in level near these times is so slow that it is not usually perceptible. In general, the duration of the apparent stand will depend upon the range of tide, being longer for a small range than for a large range, but where there is a tendency for a double tide the stand may last for several hours even with a large range of tide.

standard time
A kind of time based upon the transit of the Sun over a certain specified meridian, called the time meridian, and adopted for use over a considerable area. With a few exceptions, standard time is based upon some meridian which differs by a multiple of 15

standards and guidelines
Requirements found in a Forest Plan which impose limits on natural resource management activities, generally for environmental protection.

standing (stationary) wave
A wave that oscillates without progressing. One-half of such a wave may be illustrated by the oscillation of the water in a pan that has been tilted. Near the axis, which is called the node or nodal line, there is no vertical rise and fall of the water. The ends of the wave are called loops and at these places the vertical rise and fall is at a maximum. The current is maximum near the node and minimum at the loops. The period of a stationary wave depends upon the length and depth of the body of water and, for a simple rectangular basin, may be expressed by the formula: T = 2L / Square root(gd) in which T is the period of wave, L the length of the basin, d the depth of water, and g the acceleration of gravity. A stationary wave may be resolved into two progressive waves of equal amplitude and equal speeds moving in opposite directions.

station, control
A point on the ground whose horizontal or vertical location is used as a basis for obtaining locations of other points.

stationary wave theory
An assumption that the basic tidal movement in the open ocean consists of a system of stationary wave oscillations, any progressive wave movement being of secondary importance except as the tide advances into tributary waters. The continental masses divide the sea into irregular basins, which, although not completely enclosed, are capable of sustaining oscillations which are more or less independent. The tide-producing force consists principally of two parts, a semi diurnal force with a period approximately the half-day and a diurnal force with a period of a whole day. Insofar as the free period of oscillation of any part of the ocean, as determined by its dimensions and depth, is in accord with the semi-diurnal or diurnal tide-producing forces, there will be built up corresponding oscillations of considerable amplitude which will be manifested in the rise and fall of the tide. The diurnal oscillations, superimposed upon the semi diurnal oscillations, cause the inequalities in the heights of the two high and the two low waters of each day. Although the tidal movement as a whole is somewhat complicated by the overlapping of oscillating areas, the theory is consistent with observational data.

steamer
An artificial fly tied to represent a small minnow, baitfish, leech, etc.

stencils
Perforated sheets used with the tabulated hourly heights of the tide or speeds of the tidal current for the purpose of distributing and grouping them into constituent hours preliminary to summing for harmonic analysis. See Coast and Geodetic Survey Special Publication No. 98, Manual of Harmonic Analysis and Prediction of Tides. This analysis is now performed on electronic digital computers.

step
The nearly horizontal section which more or less divides the beach from the shoreface.

steric anoaly
Same as specific volume anomaly

stewardship
Caring for the land and its resources to pass healthy ecosystems to future generations.

stilling well
A vertical pipe with a relatively small opening (intake) in the bottom. It is used in a gauge installation to dampen short period surface waves while freely admitting the tide, other long period waves, and sea level variations; which can then be measured by a tide gauge senor inside. See float well and protective well.

stillwater level (SWL)
The surface of the water if all wave and wind action were to cease. In deep water this level approximates the midpoint of the wave height. In shallow water it is nearer to the trough than the crest. Also called the undisturbed water level.

stocking level
The number of tree in an area as compared to the desirable number of trees for best results, such as maximum wood production.

stockingfoot waders
Waders designed with sock-like feet, over which wading boots are worn.

stone
Quarried or artificially broken rock for use in construction

storm surge
The local change in the elevation of the ocean along a shore due to a storm. The storm surge is measured by subtracting the astronomic tidal elevation from the total elevation. It typically has a duration of a few hours. Since wind generated waves ride on top of the storm surge (and are not included in the definition), the total instantaneous elevation may greatly exceed the predicted storm surge plus astronomic tide. It is potentially catastrophic, especially on low lying coasts with gently sloping offshore topography. See storm tide.

storm tide
As used by the National Weather Service, NOAA, the sum of the storm surge and astronomic tide. See storm surge.

strait
A relatively narrow waterway between two larger bodies of water. See sound.

strand
The shore or beach of the ocean or a large lake. The land bordering any large body of water, especially a sea or an arm of the ocean.

strand line
An accumulation of debris (e.g. seaweed, driftwood and litter) cast up onto a beach, and lying along the limit of wave up rush.

stratigraphy
(1) The study of stratified rocks (sediments and volcanics) especially their sequence in time. (2) The character of the rocks and the correlation of beds in different localities. Stream: (1) Any flow of water; a current. (2) A course of water flowing along a bed in the earth.

stray line
Ungraduated portion of line connected with the current pole used in taking current observations. The stray line is usually about 100 feet long and permits the pole to acquire the velocity of the current at some distance from the disturbed waters in the immediate vicinity of the observing vessel before the current velocity is read from the graduated portion of the current line

stream current
A narrow, deep and swift ocean current, such as the Gulf Stream. Opposite of drift current.

strength of current
Phase of tidal current in which the speed is a maximum; also the speed at this time. Beginning with slack before flood in the period of a reversing tidal current (or minimum before flood in a rotary current), the speed gradually increases to flood strength and then diminishes to slack before ebb (or minimum before ebb in a rotary current), after which the current turns in direction, the speed increases to ebb strength and then diminishes to slack before flood completing the cycle. If it is assumed that the speed throughout the cycle varies as the ordinates of a cosine curve, it can be shown that the average speed for an entire flood or ebb period is equal to 2/pi or 0.636,6 of the speed of the corresponding strength of current.

strength of ebb
Same as ebb strength

strength of flood
Same as flood strength.

strike indicator
A small, brightly colored piece of yarn, cork or foam attached to the leader when fishing with nymphs; aids in detecting strikes.

stringer
A strip of vegetation different from surrounding vegetation, such as a stringer of aspen in a area of spruce.

stringer
A line for keeping fish after they have been caught.

stripping
A term used to describe any of the following actions: retrieving line that's on the water, pulling line from the reel in order to make a cast, or retrieving a streamer or nymph in such a way as to impart lifelike action to it.

structural geology
The branch of geology concerned with the internal structure of bed rock and the shapes, arrangement, and interrelationships of rock units. Sub-aerial beach: That part of the beach which is uncovered by water (e.g. at low tide sometimes referred to as drying beach).

structure
How the parts of ecosystems are arranged, both horizontally and vertically. Structure might reveal a pattern, or mosaic, or total randomness of vegetation.

subduction zone
Elongate region in which the sea floor slides beneath a continent or island arc. Submarine canyon: V-shaped valleys that run across the continental shelf and down the continental slope.

submerged lands
Lands covered by water at any stage of the tide. See tidelands.

submergent coast
A coast in which formerly dry land has been recently drowned, either by land subsidence or a rise in seal level. Subordinate station: A tide or current station at which a short series of observations has been obtained, which is to be reduced by comparison with simultaneous observations at another station having well-determined tidal or current constants.

subordinate current station
(1) A current station from which a relatively short series of observations is reduced by comparison with simultaneous observations from a control current station. See current station, control current station, and reference station. (2) A station listed in the Tidal Current Tables for which predictions are to be obtained by means of differences and ratios applied to the full predictions at a reference station. See reference station.

subordinate tide station
(1) A tide station from which a relatively short series of observations is reduced by comparison with simultaneous observations from a tide station with a relatively long series of observations. See tide station, primary control tide station, secondary control tide station, and tertiary tide station. (2) A station listed in the Tide Tables from which predictions are to be obtained by means of differences and ratios applied to the full predictions at a reference station. See reference station.

suborial ring
Eyelids.

subsidence
Sinking or downwarping of a part of the earth’s surface. Sub-tidal beach: The part or the beach (where it exists) which extends from low water out to the approximate limit of storm erosion. The latter is typically located at a maximum water depth of 8 to 10 m for moderate wave environments and is often identifiable on surveys by a break in the slope of the bed.

subterminal band
Stripe before tip of tail.

succession
The natural replacement, in time, of one plant community with another. Conditions of the prior plant community (or successional stage) create conditions that are favorable for the establishment of the next stage.

successional stage
A stage of development of a plant community as it moves from bare ground to climax. The grass-forb stage of succession precedes the woody shrub stage.

suitability
The appropriateness of certain resource management to an area of land. Suitability can be determined by environmental and economic analysis of management practices.

summer time
British name for daylight saving time

sunshine bass
Hybrid, Whiterock Bass - Almost a dead ringer for a Striped Bass but is easily distinguished by the stripes on the lower side, which are broken and irregular. Size: Reaches 8 or 10 pounds.

superciliary line
Line of feathers above the eye. Synonym(s): supercilium, eyebrow. In picture it is referred to as supercilium.

supercilium
Line of feathers above the eye. Synonym(s): eyebrow, superciliary line.

supraloral line
line of feathers above the lore.

surf
(1) Collective term for breakers. (2) The wave activity in the area between the shoreline and the outermost limit of breakers. (3) The term surf in literature usually refers to the breaking waves on shore and on reefs when accompanied by a roaring noise caused by the larger waves breaking.

surf (fishing)
Fishing from a beach, pier, or jedi

surf beat
irregular oscillations of water level within the surf zone with periods in the order of several minutes.

surf zone
The nearshore zone along which the waves become BREAKERS as they approach the shore.

surf zone
The zone of wave action extending from the water line (which varies with tide, surge, set-up, etc.) out to the most seaward point of the zone (breaker zone) at which waves approaching the coastline commence breaking, typically in water depths of between 5 m and 10 m.

surface gravity wave (progressive)
(1) this is the term which applies to the wind waves and swell of lakes and oceans, also called surface water wave, surface wave or deep water wave, (2) a progressive gravity wave in which the disturbance is confined to the upper limits of a body of water. Strictly speaking this term applies to those progressive gravity waves whose celerity depends only upon the wave length.

surface resources
Renewable resources that are on the surface of the earth, such as timber and forage, in contrast to ground water and minerals which are located beneath the surface.

surface water wave
see surface gravity wave (progressive).

surface wave
see SURFACE GRAVITY WAVE (PROGRESSIVE).

surfcasting
Fishing from the surf or near the surf using a specialty style rod that has a substantial butt length on the rod that enables the angler to make much more precise and longer casts.

surge
(1) Long-interval variations in velocity and pressure in fluid flow, not necessarily periodic, perhaps even transient in nature. (2) The name applied to wave motion with a period intermediate between that of an ordinary wind wave and that of the tide. (3) Changes in water level as a result of meteorological forcing (wind, high or low barometric pressure) causing a difference between the recorded water level and that predicted using harmonic analysis, may be positive or negative

survey, hydrographic
A survey that has as its principal purpose the determination of geometric and dynamic characteristics of bodies of water.

survey, photogrammetric
A survey in which monuments are placed at points that have been determined photogrammetrically.

survey, topographic
A survey which has, for its major purpose, the determination of the configuration (relief) of the surface of the land and the location of natural and artificial objects thereon.

survival
the number of animals that live through a time period (usually one year) and is expressed as a rate.

suspended load
The finest of the beach sediments, light enough in weight to remain lifted indefinitely above the bottom by water turbulence.

sustainability
The ability of an ecosystem to maintain ecological processes and functions, biological diversity, and productivity over time.

sustainable
The yield of a natural resource that can be produced continually at a given intensity of management is said to be sustainable.

sustained yield
The yield that a renewable resource can produce continuously at a given intensity of management.

swash
(1) Same as uprush. (2) A body of dashing, splashing water. (3) A bar over which the ocean washes.

swash bars
Low broad sandy bars formed by sediment in the surf and swash zones, separated by linear depressions, or runnels, running parallel to the shore.

swash channel
A narrow sound or channel of water lying within a sandbank, or between a sandbank and a shore.

swash mark
The thin wavy line of fine sand left by the uprush when it recedes from its upward limit of movement on the beach face.

swash zone
The zone of wave action on the beach, which moves as water levels vary, extending from the limit of run-down to the limit of run-up. See Figure 6.

swell
Waves that have traveled a long distance from their generating area and have been sorted out by travel into long waves of the same approximate period.

swimming lure
A lure that mimics the swimming motion of large or small bait fish.

swivel
A device used to attach two lines, a line to a lure, or even a device to prevent the twisting of the monofilament itself.

synodical month
The average period of the revolution of the Moon around the Earth with respect to the Sun, or the average interval between corresponding phases of the Moon. The synodical month is approximately 29.530,588 days in length.

syzygy
Position of the Moon when it is new or full.