1. The document discusses methodologies for collecting data on inland fisheries in India. It outlines the types of data collected, including on fish biology, the fishery, and the environment. 2. It describes the timing and locations of data collection, including at markets, landing centers, and fishing villages. Frame surveys and regular surveys are used to monitor changes. 3. The development of data collection methods in India is summarized, from initial pilot investigations in the 1950s to the establishment of standardized methodology by CIFRI in the 1990s. Water bodies are classified into three groups for stratified sampling approaches.

1. Data collection
methodologies for
Inland fisheries
Swagatika Sahoo
PG Scholar

2. 2
o Need for data collection system
o Types of data collection
o Timing and location of data collection
o Data collection system for inland fisheries in India and its development
o Methodologies used
o Issues and constraints
o Recommendations for improvement
o References

3. 3
"States should ensure that timely, complete and reliable statistics on catch and fishing effort
are collected and maintained in accordance with applicable international standards and
practices and in sufficient detail to allow sound statistical analysis. Such data should be
updated regularly and verified through an appropriate system...." (CCRF 7.4.4)
"The collection of data is not an end in itself, but is essential for informed decision-making."
(FAO Technical Guidelines for Responsible Fisheries 4:
Fisheries Management: Article 2, FAO 1997a)

4. Purposes of data collection
4
o Ideally the role of data collection is to support the monitoring of stated objectives and support for
management processes.
Extractive objectives, such
as fish protein supply or
recreational opportunities;
Social objectives, such as
income, equity of distribution
of benefits, reduction of social
conflict;
Fiscal objectives, such as
revenue and foreign earnings;
and
Conservation objectives,
such as sustainability or
biodiversity conservation.
Most fisheries are managed for a mix of these objectives. It is, therefore, important to agree on a common
approach to the fishery so that data collection systems serve the greatest number of interested
parties.
o Objectives of inland fishery management include:

5. Types of data and information
5
Data are raw numerical values that
must be analyzed to become
information.
Information may also be non-numerical and deal
with such questions as whether it is the men or
women who fish or whether a particular species
migrates.
Absolute
data
• which attempts to assign values to such
variables as catch that are as close to
reality as possible. Absolute values are
generally a snapshot of the situation at a
point in time.
Relative
data
• which attempt to trace the movement of
values over time from a baseline. The
baseline itself may be an absolute value
or one that is selected arbitrarily in the
time series.
The fish,
including data
and
information on
feeding,
breeding,
growth and
mortality as
well as any
migrations
and other
aspects of
biology;
The fishery,
including
statistics on
landings and
effort,
information on
gear and its
performance,
information on
behavior and
income of the
fishers and
their families;
The
environment,
including
information on
water quality
and quantity
the degree of
modification
of aquatic
habitats and
ecosystems.

6. TIMING OF DATA AND INFORMATION COLLECTION
Studies and surveys are expensive and detailed operations usually designed
6
o A frame survey divides a river or lake into various strata or
zones according to ecological, fishery or social
characteristics, identifies sampling locations that are
typical of the various strata, and lays down a schedule for
the timing of sampling. Division of the area into strata
makes it easier to group sampling sites and interpret the
data collected from them.
o Regular surveys are carried out at regular intervals to
monitor changes following major studies. A sampling
frame may be used to select the number and location of
the sampling sites.
o Daily/weekly collection of data is used to establish local
trends at individual markets and landings. A sampling
frame may be used to specify landings and markets that
are main data collection points.
In statistics, a sampling frame is the source material or
device from which a sample is drawn. It is a list of all
those within a population who can be sampled, and may
include individuals, households or institutions.

7. LOCATION OF DATA AND INFORMATION COLLECTION
7
Markets, which are the great concentration point of the fish sold and passing through the
commercial network.
They are particularly useful in diffuse fisheries where there are no defined landings.
Market surveys carry the danger of double counting, as the same fish may appear more
than once in the same market or in successive markets in the chain.
Landing centre, which are the primary collection point of fish landed. These are particularly
valuable in lakes or large rivers where definite points have developed for landing and sale of fish.
They collect data primarily on quantity of fish landed by the fishery and can also be used to gather
data on species, weight, length and sexual condition. They are also good for the collection of data on
the types of gear in use.
Landing data are also incomplete in that it misses the often considerable amount of fish consumed by
the fishers, their families and associated communities (auto consumption).
Fishing villages, through family and household surveys, which can detect sources of fish that
are not dependent on landings and boats but which are collected from small water bodies by women
and children. Such surveys are also useful for understanding how the fishery works.
They can supply data on gear use patterns and on the social and economic organization of the
fishers. Individual fishers, who are difficult to sample on a regular basis in most fisheries. They are
however the best source of data on the performance of individual gear use and on the types and
sizes of the fish caught.
They can also be helpful in providing information about auto consumption patterns and the allocation
of work among participants in the fishery.

8. DIFFERENT METHODS USED FOR DATA COLLECTION FROM INLAND
FISHERIES
FISHERIES-
INDEPENDENT METHODS
Biological sampling for age ,growth and
maturity information
Angler surveys with probabilistic sampling
The use of hydroacoustics to estimate
fish numbers
Use of eDNA to detect the fish species
present and their relative abundance
FISHERIES DEPENDENT
METHODS
Registration
Logbooks
Questionnaires
interviews
Direct observations
Scientific research
8

9. 9
Schematic representation of the chain
of events in design and
implementation of fishery data and
information collection systems.
Source: FAO

10. Status of Inland fisheries in India
10
• Inland water resources in India are diverse and comprised
of 29,000 km of rivers, 0.3 million ha of estuaries, 0.19
million ha of backwaters and lagoons, 3.15 million ha of
reservoirs, 0.2 million ha of floodplain wetlands and 0.72
million ha of upland lakes.
• India is the second largest producer of inland fishes and the
second largest aquaculture nation in the world.
• The total fish production of India touched 13.8 MT in 2018-
19 with a contribution of 8.92 million tonnes (about 71%)
from inland sector. Engaging over 14.5 million people at the
primary level and almost twice the number along the value
chain.
1. Ensuring food security
2. Economically viable exploitation
3. Resource conservation by
meeting MSY
This calls for strategic planning on
the basis of scientific assessment
of various biological, social and
economic indicators.
Exploitation

11. 11
the inland fisheries statistics in India based on
1. market arrivals furnished by the states
2. water area leased
3. stocking of seed
The National
Commission on
Agriculture (1976)
the data collected from these resources are sometimes neither comparable nor aggregated at
national level as their concepts and definitions vary from region to region.
There is a strong need for evolving a scientific methodology of data collection with uniform concepts
and definitions.
The success of strategic planning in assessment
largely depends upon the availability of reliable data.

12. 12
1991
1984
1978-81
1973-75
1962-63
Sept-
1958
April-1956
1955-56
a pilot investigation
was launched by ICAR
in two districts of
Hyderabad state for
developing sampling
techniques for inland
fisheries resource
estimation.
the Directorate of the National
Sample Survey took up the
survey work in Orissa to evolve
suitable sampling techniques
for estimation of fish
production.
The NSSO conducted a
survey covering 3 districts
one each in West Bengal,
Tamil Nadu and Andhra
Pradesh for estimating
the catch from
impounded water as well
as riverine resources by
enquiry method
a centrally sponsored scheme
was launched in 8 states to
evolve standardization
methodology for collection of
inland fisheries statistics in the
country and its implementation
was entrusted to CIFRI,
Barrackpore
The CIFRI Barrackpore has brought out
a bulletin number 58 (revised) in 1991
on methodology for collection and
estimation of inland fisheries statistics in
India, to provide guidelines on collection
of data and estimation procedures with
associated degree of reliability at
national level.
the Government transferred
the work from ICAR to the
Directorate of National
Sample Survey (NSSO)
IASRI and CIFRI carried
out a pilot survey in one
district of West Bengal
covering 24 paragans.
The data were collected
both by enquiry and by
physical observations.
DEVELOPMENTS OF INLAND CATCH ESTIMATION METHODS IN INDIA
These sampling techniques
later formed the basis of the
pilot survey undertaken by the
NSSO in 1962-63, in 3 districts
of Orissa viz. Cuttack,
Sambalpur and Mayurbhanj
based on IASRI.

13. 1992-1997 1998-1999 2002-2012
13
during 8th Plan, DAHD&H
entrusted the development of
uniform concepts, definitions and
terminologies for various inland
fishery resources and a suitable
and standardized methodology for
collection and estimation of inland
fishery resources and catch to
Central Inland Fisheries
Research Institute(CIFRI),
Barrackpore in collaboration with
the states.
Now , A New Department Called
Department of Fisheries has been created
out of the erstwhile Department of Animal
Husbandry, Dairying & Fisheries
Ministry of Fisheries, Animal Husbandry and
Dairying is a newly formed ministry in
India. It was formed in May 2019 by Modi
government from the department of same
name under Ministry of Agriculture and
Farmers Welfare.
May 2019
The methodologies have been developed
and tested in various States during 8th
and 9th Plans.
The resources assessment survey work
and catch assessment survey work have
been completed in 158 waterbodies and
56 districts respectively.
The Central Sector Scheme on “Strengthening
of Database and Information Networking for
the Fisheries Sector” is in operation during the
Tenth and Eleventh Plan. As per the Scheme,
the respective State Governments collect
the inland fish catch statistics and transmit
the estimates to the Department of Animal
Husbandry and Dairying (DAHD), Ministry of
Agriculture, Government of India .These
estimates are then submitted before the
Technical Monitoring Committee of the
DAHD&F .

14. 14
o The Central Inland Fisheries Research Institute (CIFRI), Barrackpore in 1991 devised a methodology
for collection of data relating to some important still water areas.
o This involves dividing water sources into two categories namely, fresh water and brackish water
bodies each with a distinct ecology, and classifying them further into three groups according to the
level of production.
o Different sampling methods are adopted for assessment of fish production in each group. There is still
a large data gap in coverage not only geographically but also in terms of several sources of
inland fisheries such as rivers, canals, etc.
CIFRI Methodologies for data collection
Inland fisherman Fishery survey
officer
State government
Department
of fisheries,
MoA, GOI
Schematic diagram of information flow in India

15. Classification of inland fisheries resources for production assessment
◉ Fresh water resources
ponds and tanks, large irrigation
tanks, lakes, reservoirs, beels, river,
streams
15
The DAHD&F publishes the national inland fish production statistics. The methodological support is
given by the CIFRI as when required.
Inland water bodies are broadly classified into two categories:
◉ Brackish water resources
estuaries, lagoons, “bheries”.
all those potential class of water bodies need coverage under catch assessment programs are
being classified for the execution of the methodology in order to provide firm, reliable and
statistically sound data base on inland fisheries. Water bodies that marginally contribute to catch is
not included in this method.

16. 16
Groups of
Waterbodies
Group 3
Group 1
(Water bodies up to 10
ha at full tank level)
1.Large Irrigation Tanks
2. Reservoirs and check dams
3. Lakes
4. Ox-bow lakes / Meanders / Channel Scars
1. Rivers
2.Canals
3.Estuaries
4.Lagoons
5.Back waters
1.Aquaculture ponds and tanks
2. Brackish water
impoundments
3. Waterlogged areas
Group 2
(Water bodies above
10 ha at full storage
level)
A water body considered a tank in
one state is known and grouped
as reservoir in another state.
There are no uniform criteria
adopted by the States. This lacuna
makes the data incohesive and
noncomparable between the
States and to pool at the national
level.

17. 17
Sampling methodology
Since the productivity varies from type to type of water bodies, separate sampling methodologies,
type specific, are followed.
o The whole state is divided into three nearly homogeneous groups called strata (each stratum
containing a number of districts) on the basis of certain characteristics such as climate,
rainfall, soil quality etc.
o Strata should be formed in such a way that geographical contiguity of districts within stratum
is maintained.
o From each stratum a sample of 30% districts may be selected at random for the survey.
Further, sampling within each selected district is carried out.

18. 18
There may be two situations:
(1) resource may be estimated and
(2) resource data may be available from inventory or some other source
In both the cases stratified three-stage sampling where districts, clusters and ponds are first, second
and third stage units of selection respectively is adopted. However, in the first case we need to collect
data on resource whereas in the second case we need not do it
Ponds
Clusters
Districts
Units of selection in stratified three-stage sampling
Sampling procedure for Group I water bodies

19. 1.Collection of Resource data
19
Sampling frame should
be prepared for each
selected district by
making a list of villages.
In a particular district, villages
having inland water bodies of
may be highlighted and clusters
of five nearby villages formed
from among the pond bearing
villages.
From these clusters a
sample of nine clusters
is selected by random
sampling for assessment
of water spread area.
A further sampling of
five ponds (under
utilization for fishery)
in each cluster is
recommended for
estimation of fish
production.
1
year
monthly

20. 2. Alternative procedure( data available)
20
o It happens sometimes that information on the total resource is available from other sources. In
that case there is no need of estimation of area under different categories of water bodies.
o The data on
are available.
o In such cases the catch data will be collected as per the same procedure outlined above, i.e.
sampling of five ponds in each cluster is recommended for estimation of fish production.
o

21. 21

22. 22

23. Sampling procedure for group II water bodies
23
Investigations have shown that two types of exploitation pattern are adopted in these water bodies.
(1) Water bodies, which are harvested for a short interval extending from a fortnight to about a
month during the year.
Examples- small reservoirs and lakes
under the preview of state departments and exploitation is affected either by auctioning them to
private contractors under certain terms and conditions or exploited departmentally by engaging contract
labour. Hence, the bulk of harvest is a one time operation. Data from such water bodies are
collected on total enumeration basis.
(2) Water bodies, which are exploited round the year by fishermen cooperatives or individual
fisherman on the basis of licenses, free fishing, royalty or any other such mode.

24. 24
o There are two types of approaches for estimation of monthly, quarterly and annual catch
depending on the exploitation practices and disposal of catch.
o If individual fisherman exploits the water bodies and catch record may be available for each
operating unit separately, the is adopted.
o If the catch cannot be recorded by units operated and only total catch, which is landed for disposal,
can be assessed, then is adopted.
o However, first we will try to get the information about the water body and then we have to
specify the “choice of sampling units” which may be either “Fishing village” or “Landing
centre”. Based on this information the monthly, quarterly and the annual catch will be estimated
adopting the appropriate technique.

25. 25
Collection of Inventory Data
the inventory of village-wise operating units is made
in fishing village approach. Here data from all the
fishing villages by the side of the water body
have to be collected. Information should be
collected from each household of the village.
Data to be collected
head of the household
family size (adult & children)
Fishing as occupation
number and type of boats
type of gears and their number
used by the household
mode of disposal of the catch.
Fishing Village Approach

26. 26

27. 27
Collection of catch data
• A few villages (25%-30% with a minimum of two villages) are selected at random to record
the catch on sampling days of a month.
• Fortnightly, systematic sampling is followed in selection of days, if fishing is done everyday
in the month; otherwise random sample of fishing days is taken from each fortnight.
• On the day of sampling, the investigator is required to record the no. of units operated, total
catch as well as species-wise catch along with other details from selected water units. In
brief, this procedure can be described as stratified three stage sampling where selection of
fishing villages is the first stage, sample days as second stage and units observed as third
stage of selection
Units
observed
Sampling
days
Selection
of fishing
village
1 2 3

28. 28
1. Collection of Inventory Data
Here, data from all the landing centres of the water body under the district have to be collected.
2. Collections of catch data
o In landing centre approach, it is difficult to record the catch unit-wise. A few landing centres
will be selected for collection of catch data. From each selected landing centre, the total
catch as well as species-wise catch for the day can be noted.
Landing Centre Approach

29. 29
The observation of catch is made by the following procedure:
o A few landing centres (25%-30% with a minimum of two) are to be selected from the total
landing centres of that water body.
o Further, sampling of days in months is made fortnightly adopting systematic sampling of
two consecutive days for collection of catch data, if fishing is done everyday in the month;
otherwise random sample of days is taken from fishing days in each fortnight.
Time strata Days in a month
1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
2 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

30. 30
o Each selected landing centre is physically observed on two consecutive days in each of the first
and second fortnight during the month. On a selected day of sampling at a centre, data are collected
during 12.00 to 18.00 hr and on second day from 06.00 to 12.00 hrs. Data on night landings, if any, in
between the consecutive days are collected by inquiry on the second day.
o On the selected day of observation, the investigator should collect information on the total catch
landed and species composition. He should also ascertain the number of fishing holidays
observed during the last month.

31. 31

32. Sampling procedure for group III water bodies (Rivers, Streams,
Canals, Estuaries etc.)
32
• The water bodies under this group sustain multi gear and multi species fishery exploited by
artisanal fishermen operating on the entire area of the system making the estimation rather
cumbersome.
• Most of the water bodies do not have well established landing centres where fishermen may
land their catch.
• In some of the cases, entire bank of the river act as landing point for them and they directly take the
catch to the wholesale or retail market for final disposal.
• However rivers like Ganga and estuaries like Hooghly-Matlah have some landing centres at
some points which can be considered for collection of data.
• Fish catch from this group of water bodies is generally negligible in most of the states.

33. 33
• Sampling frame for this group is prepared by enlisting district-wise, all the fishing villages/landing
centres in each of the strata. 25 to 30% of these units are selected by random sampling from amongst
the selected districts of each stratum at the second stage.
• For each selected unit 2 to 4 sampling days within a month are further selected at the third stage for
collection of catch data
• Hence, the above procedure may be termed as stratified three stage sampling where district-wise
villages, days of sampling and units observed form the first, second and the third stage of sampling
respectively.
Units
observed
Days of
sampling
District
wise
villages
The observation of catch is made by the same procedure as adopted for Group II water bodies, where
fishing is done throughout the year.

34. 34

35. APPLICATION OF INFORMATION FOR SPECIFIC PURPOSES
National decision
making
Management of
fish stocks
Fishers and their
communities
Conservation and
rehabilitation
35
• Evaluation of gross
contribution of fisheries to
the economy
• How much funding to
devote to the sector
• Whether to build a
sampling site/research
facility
• Amount that can be
equitably extracted as tax
• Allocation of water
between different users of
resources
• Assesmnent of
general health of
fishery through trends in
catch-weight-
composition
• Management of MSY for
species
• Introductions of other
stocks
• Equitable
distributions of
access and benefits
• ensuring social
justice for women
and child
• Avoidance of
conflicts between
stakeholders
• Improvement of water
quality
• Assessment of
impacts of engineering
works
• Establishing
environmental flow
scenario
• Need for and setting
up of protected areas

36. 36
Issues of the inland
fishery statistical
system
Unlike marine sector, inland fisheries cannot claim a satisfactory status with
regard to data collection;
Open access system nature of inland open-waters;
Multiple usages & multiple-ownership;
Poor understanding of requirements of users;
Inadequacy in basic database at the state level;
The data collected from inland fishery resources of different states are
sometimes neither comparable nor compilable at Central Level;
Unregulated fishing practices;

37. constraints of the inland fishery statistical system
37
Incomplete and incorrect or unreliable data at state level
Lack of coordination among stakeholders
Lack of uniform policy for resource management
Incompatibility of data
Lack of standardized data collection and compilation methodologies and tools.
Poor accessibility to fishery resources in upland regions
Lack of adequate skilled manpower
Lack of priority on HRD in open-water issues

38. 38
4
3
2
1
Improving the quality of inland fisheries statistics
• Instead of doing additional surveys,
countries should review their existing
statistics using existing information (and
involving the relevant stakeholders in the
process).
• Reasonable estimates of the importance
of the sub-sector can be obtained using
existing local information, comparative
data from elsewhere and fishery
independent information.
• This information can be obtained from
locally available maps and using remote
sensing imagery which is already
available (although not necessarily in
Departments of Fisheries).
• The information should be kept in digital,
geo-referenced format, so that it can be
used in a GIS (Geographic Information
System).
Population census data should be
compared with resource availability. If
population census data will already be
digitised and geo-referencing enabled
then it can be analysed in a GIS –
enabling computer aided analysis of
relationships between populations
and resources.
These considerations are basic and
country specific.
• Areas with better economic
development tend to be less dependent
upon inland capture fisheries
• The level and kind of agricultural
development. Rice-farming usually has
considerable fisheries activities
associated with it.
• Access to markets. This is important
because fishery resources will be
exploited only to the level of demand.

39. References
39
◉ CCIFRI , BULLETIN 58 (REVISED EDITION) - February 1991, Methodology for Collection and Estimation of Inland Fisheries
Statistics in India
◉ FAO, EIFAC Technical Paper No. 33 , GUIDELINES FOR SAMPLING FISH IN INLAND WATERS
◉ CSO-MFS-2011 MANUAL ON FISHERY STATISTICS e Government of India Ministry of Statistics and Programme
Implementation Central Statistics Office Sansad Marg, New Delhi www.mospi.gov.in
◉ 3. OBJECTIVES OF DATA COLLECTION (fao.org)
◉ REPORT OF THE WORKING GROUP ON FISHERIES FOR THE ELEVENTH FIVE YEAR PLAN (2007-2012)
◉ 8. FRAME SURVEYS (fao.org)
◉ Review of data collection systems in BOBLME countries by Kim Stobberup Bay of Bengal Large Marine Ecosystem Project –
BOBLME
◉ Vehanen, T.; Piria, M.; Kubečka, J.; Skov, C.; Kelly, F.; Pokki, H.; Eskelinen, P.; Rahikainen, M.; Keskinen, T.; Artell, J.;
Romakkaniemi, A.; Suić, J.; Adámek, Z.; Heimlich, R.; Chalupa, P.; Ženíšková, H.; Lyach, R.; Berg, S.; Birnie-Gauvin, K.; Jepsen,
N.; Koed, A.; Pedersen, M. I.; Rasmussen, G.; Gargan, P.,Roche, W. & Arlinghaus, R. 2020. Data collection systems and
methodologies for the inland fisheries of Europe. FAO Fisheries and Aquaculture Technical Paper No. 649. Budapest, FAO.
https://doi.org/10.4060/ca7993en
◉ Data Requirements for Inland Fisheries Management (fao.org)

40. 40