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Glossary
| WAVE(S) |
Two-month sampling
periods (e.g. Wave 1=January/February) |
| GEOGRAPHICAL AREA - STATE/AREA |
Areas are arranged in geographical order by
subregion. For example, the option "North
Atlantic by State" will give you catch for
the five states listed after that option (Maine
through Massachusetts) on a state-by state basis.
The "North Atlantic" option will give
you the catch summed across the five states.
Florida is divided into two regions (east and
west) in our survey, as is California (southern
and northern). Selection of "Florida" under
either subregion will give you the total for
the whole state. Options for "Pacific Coast
by Sub-Region" (S. California, N. California,
Oregon, and Washington) and "Atlantic Coast" (Maine
to East Florida) have been added to this selection
group.
MRFSS sampling began in Puerto Rico in 2000 (Caribbean
subregion). |
| Type of Catch |
Type A catch are fish brought
back to the dock in a form that can be identified
by trained interviewers.
Type B1 catch are fish that
are used for bait, released dead, or filleted
-- i.e. they are killed but identification
is by individual anglers.
Type B2 catch is fish that
are released alive - again, identification
is by individual anglers.
Thus,
- TOTAL CATCH = Type A + B1 + B2,
- HARVEST = Type A + B1,
- LANDINGS = Type A only,
- DISCARDS = Type B1 only, and
- RELEASED ALIVE = Type B2 only.
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| LENGTH DISTRIBUTIONS |
Length distributions are available for selected
species by inch group. Inches groups contain
fish that were from X.00 to X.99 inches long. For
example, inch group 9 means fish that are between
9.00 and 9.99 inches. These lengths are FORK
lengths.
Length distributions are based on cells (state/wave/fishing mode/fishing area/species)
where at least 5 individual fish measurements were taken. Cells with 5 or less
measurements are ignored (i.e. no substitute lengths are used as is done in some
analyses. This was done so that distributions are not skewed by unrepresentative
fishing modes, areas, or waves.
The raw length distributions are weighted by the estimated
number of fish harvested (catch type A + B1) in each
cell so that the distributions are correctly summarized
across time periods and geographic areas. |
| FISHING AREA |
INLAND means inshore saltwater
and brackish water bodies such as bays, estuaries,
sounds, etc. It does not include inland freshwater
areas.
STATE TERRITORIAL SEA is a zone
extending three nautical miles from shore for all
states except for Puerto Rico and the Gulf coast
of Florida where the seaward boundary is 3 marine
leagues (approximately 10 statute miles). The state
territorial seas do not include inland areas.
STATE WATERS is the combination
of inland and state territorial seas.
The FEDERAL EXCLUSIVE ECONOMIC ZONE (EEZ)
is contiguous to the State Territorial Seas of all
the United States and its possessions and extends
seaward 200 nautical miles measured from the baseline
from which the Territorial Sea is measured.
OCEAN is a combination of the State
Territorial Sea and the EEZ |
| TYPES OF FISHING (MODE) |
For a detailed breakdown of all modes, select ALL
MODES BY MODE.
North Carolina is the only state to break SHORE mode
into BEACH/BANK and MAN MADE.
The FOR-HIRE sector sampling varies over time. To
see detailed breakdown of for-hire modes, select
ALL MODES BY MODE:
- 1981 – 1985: PARTY/CHARTER
mode only. All for-hire boats (charter and
head/party boat) were sampled as one category;
a single PARTY/CHARTER mode estimate was produced
(undifferentiated).
- 1986 - 2004: PARTY/CHARTER mode continued
in the Northeast states, Maine to Virginia. In
the Southeast (North Carolina to Florida and the
Gulf of Mexico states), CHARTER BOATS (only) were
sampled by MRFSS. Party (head) boats are
surveyed by Southeast Head Boat Logbook Program
which began in 1986 (not presenting in these estimates).
2005 – ongoing: CHARTER and PARTY (head)
boats are sampled independently by the For-Hire Survey
and stratified Angle Intercept Survey; separate
CHARTER and PARTY (HEAD) boat estimates are produced. Undifferentiated
PARTY/CHARTER sampling is no longer performed. |
| PSE |
Proportional Standard Error (PSE) is automatically
included with requested information , with one exception.
The exception is the PSE for mean lengths.
- Calculations of mean lengths involve weighting
mean lengths by the estimated number of fish in
a cell (state/wave/fishing mode/fishing area/species).
- These calculations are quite complicated and
rely on various assumptions.
- Because of the assumptions, it is better that
these calculations be made on a case-by-case basis.
- Use of mean lengths is not as useful as length
distributions and is not used widely.
- Because of its limited use, we do not expect
the absence of the PSE to cause any problems or
lead to incorrect conclusions about a fishery.
The PSE, or proportional standard error, expresses
the standard error of an estimate as a percentage
of the estimate and is a measure of precision.
- Precision refers to the dispersion of sample
measurements used to calculate an estimate and
the resulting variability in the estimate.
- Large PSEs indicate high variability around estimates
and therefore low precision.
- It is desirable to have small PSE's and more
precise estimates.
- There is a direct relationship between precision
and sample size.
- When we group year, state, wave, or mode estimates,
sample size increases and so does precision.
- Catch estimates for commonly caught species that
show up in the marine recreational fishery often
are more precise than for rare event or pulse fisheries.
Data users should consider the width of confidence
intervals surrounding estimates before drawing any
far-reaching conclusions from point estimates.
- A confidence interval is calculated as the estimate
minus 1.96 times the standard error (the lower
limit) and the estimate plus 1.96 times the standard
error (the upper limit).
- A 95% confidence interval means we are 95% sure
that the true value lies between the lower limit
and the upper limit.
|
| WEIGHT DATA |
USE CAUTION WITH WEIGHT DATA
Weight estimates are minimums and may not reflect
the actual total weight landed or harvested.
MRFSS weight estimates are calculated by multiplying
the estimated number harvested in a cell (year/wave/state/mode/area/species)
by the mean weight of the measured fish in that cell.
Sometimes we have an estimate of harvest but no mean
weight, either because
- the harvest is all reported by the anglers (B1),
or
- because for some reason the interviewers couldn't
weigh any fish (fish too big, already gutted and
gilled, etc.).
If a cell is missing a mean weight, and if we have
at least two fish measured in the state (all fishing
areas and modes combined),
- We substitute the mean for the whole state for
that wave.
- We need two measured fish to get a variance estimate.
After state substitution, if the mean weight is
still missing,
- We use the mean from the whole subregion for
that wave.
- The "two fish rule" still applies.
After subregional substitution, if the mean weight
is STILL missing, we give up and leave a missing
weight estimate. At that point,
- It is up to the user to determine whether to
substitute, and
- What substitution is most appropriate to use
(a mean from the preceding and following waves,
the whole year, same wave over years, whole Atlantic & Gulf
coast, some complicated regression model, whatever).
- We don't make those decisions because the information
needs and sensitivity of the data vary among species.
The phenomenon of missing weights is more widespread
with rarely caught species and with large fish (i.e.
tunas). The existence and/or extent of missing weights
for your query can be examined by requesting data at
the cell level: (by year/wave/state/by mode/by area/by
species (time series)). |
| CENSUS DATA |
2000 Update
The effort estimates (numbers of trips) for the
Marine Recreational Fishery Statistics Survey are
calculated based on a random sample of residents
of households in coastal counties. The average number
of recreational saltwater fishing trips per household
is calculated and this average is expanded by the
number of households in the county. The number of
households is based on annual projections made by
the Survey of Buying Power (Bill Communications).
Official Census Bureau counts of households for the
2000 Census have been recently released and where
these numbers differed with the projections, the
count of households has been updated to reflect the
Census Bureau figure. These updates will result in
some small changes to the effort, and hence also
to the catch, estimates.
2005-2006 Hurricane Katrina Update
On June 7, 2006, the United States Census
Bureau published special estimates to assess
the impact of Hurricanes Katrina and Rita
on population and demographic characteristics
of Gulf Coast communities (http://www.census.gov/Press-Release/www/emergencies/index.html). These
estimates are not considered part of the Census Bureau’s
official estimate series. Rather, they were
produced using specially designed methodologies to
assess the impacts of hurricane events on population
sizes of affected counties (for a complete description
of the methodology used by the Census Bureau, please
refer to http://www.census.gov/Press-Release/www/emergencies/impacted_gulf_methodology.html).
While not part of the official estimate series, these
special estimates are the most accurate approximation
of hurricane impacts on Gulf Coast populations. As
such, they have been incorporated into the procedures
used to estimate recreational fishing effort and
catch, beginning with wave 5 (September/October),
2005 and continuing through 2006. |
| PARTICIPATION |
The MRFSS makes estimates of participation for three
categories based on area of residence:
- From January-April and November-December, coastal
county residence means anglers from counties within
25 miles of the coast.
- From May-October, coastal county residence means
anglers from counties within 50 miles of the coast.
- In North Carolina, the coastal zones are within
50 and 100 miles of the coast, because of the fishing
patterns in that state.
- Non-coastal counties are counties within the
state but not in the defined coastal zone.
- Out-of-State means people from other states or
countries who came to the state and fished.
Summing across categories and geographic areas:
- All participants are additive within a state.
- Coastal and non-coastal county residents are
also additive across states and sub-regions.
- Out-of-state participants should NOT be added
across states or regions.
- An out-of-state participant could have fished
in more than one state that is not his or her state
of residence.
Addition of out-of-state participants across states
may result in double counting of some individuals. |
| SAMPLE COVERAGE |
Currently, the recreational fishing statistics program conducted by the NMFS includes the Atlantic coast (ME-East FL), Gulf coast (LA-West FL), Puerto Rico and Hawaii. Data presented in the queries are those from only these surveys. Data from other NMFS and state surveys are not included in the query. Care is advised when comparing catch estimates across an extended time series because of differences in sampling coverage through the years.
In the South Atlantic and Gulf sub-regions (NC- LA) party boat catch data have not been collected since 1985, so estimates for these sub-regions only include charter boats in the for-hire sector. Prior to 1998, on the Pacific coast, ocean boat trips and salmon trips were not sampled during certain waves because they were surveyed by state natural resource agencies. West Pacific U.S. territories have not been included in the national survey program since 1981. Hawaii was not surveyed between 1981 and 2002. The U.S. Caribbean was not surveyed between 1981 and 2000. Alaska conducts an annual mail survey in place of the NMFS’ program. Marine recreational fishing in Texas is monitored by the Texas Parks and Wildlife Department and has not been surveyed by the NMFS’ survey program since 1985.
Historically, only about five percent of the annual recreational catch on the Atlantic and Gulf coasts is taken during Wave 1 (Jan/Feb). Costs to sample these months are very high due to low fishing activity. Therefore, in Jan/Feb of 1981 the surveys were not conducted in any region. In 1982, Jan/Feb data collection resumed on the Pacific and Gulf coasts and also on the Atlantic coast of Florida. With a few exceptions the recreational statistics program has not collected data in Jan/Feb on the Atlantic coast north of Florida since 1980.
Time periods when the marine recreational statistics program has not been conducted: Nov/Dec (ME & NH) - 1987 to present; Mar/Apr (ME & NH) - 1986 to present; Jan/Feb (Northern CA & OR) – 1994; Jan/Feb (Southern CA & OR) – 1995 Nov/Dec (OR) – 1994; Nov/Dec (WA shore modes) – 2003; July - Dec (OR shore modes) – 2003; All Waves (CA - WA) - 1990 to 1993, 2004 to present; All Waves (WA) - 1993 to 1994.
The NMFS Beaufort Laboratory conducts the Headboat Logbook Survey to provide headboat (partyboat) catch and effort for the Southeast Region (NC-TX). Data are available from:
Southeast Fisheries Science Center
Beaufort Laboratory
101 Pivers Island Road
Beaufort, NC 28516-9722
The Texas Parks and Wildlife Department has conducted their own survey of marine recreational fisheries since 1974. Estimates for Texas are available from:
Texas Parks and Wildlife Department,
8400 Smith School Road,
Austin, Texas 78744
The Pacific states conduct surveys of salmon fishing, ocean-boat fishing, and California passenger fishing vessels. Estimates for these fisheries are available from:
Pacific States Marine Fisheries Commission,
45 SE 82nd Drive, Suite 100,
Gladstone, OR 97027
The Alaska Department of Fish and Game conducts surveys of recreational fishing in that state. |
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