A methodology manual



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Ecosystem services:





LSE

UG

Service

Private tree plantation

Agriculturist / Plantation owner

Check on soil erosion ( due to contours )

Private tree plantation

Honey collector

Flowering of plantation crops leads to increased availability of honey


Ecosystem bads:


LSE

UG

Common name

Dis-use

Agricultural land / Plantation

Agriculturist / Plantation owner

Rat

Nuisance

Agricultural land / Plantation

Agriculturist / Plantation owner

Hare

Nuisance

Agricultural land / Plantation

Agriculturist / Plantation owner

Bandicoot

Nuisance

Agricultural land /

Plantation



Agriculturist / Plantation owner

Bonnet macaque

Nuisance

Agricultural land /

Plantation



Agriculturist / Plantation owner

Mite

Crop pest


Agricultural land /

Plantation



Agriculturist / Plantation owner

Caterpillar

Crop pest

Agricultural land /

Plantation



Agriculturist / Plantation owner

Stem borer

Crop pest

Agricultural land /

Plantation



Agriculturist / Plantation owner

Beetles

Crop pest

Agricultural land /

Plantation



Agriculturist / Plantation owner

Tree borer

Crop pest

Agricultural land /

Plantation



Agriculturist / Plantation owner

Terminal leaf eater

Crop pest

Agricultural land

Agriculturist

Sparrow

Crop pest

Agricultural land

Agriculturist

Peafowl

Crop pest

Agricultural land

Agriculturist

Quail / Partidge

Crop pest

Agricultural land /

Plantation



All UGs

Ticks

Nuisance

( Plantation refers to private tree plantations )


Ecosystem disservices :
Agricultural lands and private tree plantations are repository of nuisance species and pests ( See above ).
9. FORESTS

While from an ecological perspective we may discriminate several types of ecotopes with natural or human impacted forest vegetation, the local people treat this as a single type. They however recognize within the broad forest category different habitat preferences – for instance, that some genera like Gymnacranthera and Pandanus are restricted to swamps, others to streamsides, others to hill tops, and so on. The government forest department, on the other hand, treats all land under its legal control, regardless of whether it is under grassland, Casuarina plantation or natural forest as forest.


9.1 Measurements

Apart from soil and water related parameters mentioned earlier, the scientific measurements would focus on standing biomass, harvests and biodiversity. Methods of biodiversity measurements would be considered below under section 14. Standing biomass may be measured through quadrats or plotless methods such as point centred quarter method. In the latter method a series of transects are laid from randomly chosen starting points along random directions of compass with a sampling point fixed at some predetermined interval, such as 100 meters. At this sampling point distance, girth and height of trees nearest to the point in each of the four quarters are measured; a tree being defined as a plant with a diameter of 10cm or more at a height of 130cm. Standard textbooks on eoclogical methodology provide other details including computational formulae. Other measurements such as leaf litter and regeneration may also be undertaken.


Table 13. Ecosystem goods/ services/ bads/ disservices associated with forest lands of Mala study cluster
Ecosystem goods:


LSE

UG

COMMON NAME

SCIENTIFIC NAME

CATEGORY

USE

M/L/B

Evergreen forest

NTFP collector

Manthapuli

Garcinia cambogia

NTFP

Pickles

M

Evergreen forest

NTFP collector

Bherundi

Garcinia indica

NTFP

Food

B

Evergreen forest

NTFP collector

Vatehuli

Artocarpus lakoocha

NTFP

Pickles

B

Evergreen forest

NTFP collector

Rampatre

Myristica malabarica

NTFP

Condiment

M

Evergreen forest

NTFP collector

Dalchini

Cinnamomum verum

NTFP

Condiment

M

Evergreen forest

NTFP collector

Dhupa

Vateria indica

NTFP

Varnish

M

Evergreen forest

NTFP collector

Norekai

Sapindus laurifolius

NTFP

Detergent

B

LSE

UG

COMMON NAME

SCIENTIFIC NAME

CATEGORY

USE

M/L/B

Evergreen forest

NTFP collector

Karimenasu

Piper nigrum

NTFP

Condiment

B

Evergreen forest

NTFP collector

Mavu

Mangifera indica

NTFP

Food

B

Evergreen forest

NTFP collector

Alale

Terminalia chebula

NTFP

Tanning

L

Evergreen forest

NTFP collector

Mundaga

Pandanus

NTFP

Mat making

L

Evergreen forest

NTFP collector

Bettha

Calamus

NTFP

Basket making

L

Evergreen forest

NTFP collector

Vate

Ochalandra

NTFP

Basket making

L

Evergreen forest

Firewood collector

Honne

Callophyllum apetalum

Firewood

Fuel

L

Evergreen forest

Agriculturalist







Leaf liiter

Manure

L

Evergreen forest

Agriculturalist

Ratsnake

Ptyas sp.

Reptile

Pest control (Predator)




Evergreen forest

Fishermen

Karekai

Randia dumatorum

Bush

Fish poison

L

Evergreen forest

Honey/beewax collector







Honey and beewax




L

Evergreen forest

Basket makers

Nedil

Lea indica

Climbers

Basket makers

B

Evergreen forest

Basket makers

Renjir

Calycopteris floribunda

Climbers

Basket makers

B

Evergreen forest

Basket makers

Ithalbooru

Desmos lawii

Climbers

Basket makers

B

Evergreen forest

Basket makers

Pandil

Uvaria narum

Climbers

Basket makers

B

Evergreen forest

Basket makers

Perbooru

Tylophora indica

Climbers

Basket makers

B

Evergreen forest

Basket makers

Madir

Hippocratia arnottiana

Climbers

Basket makers

B

Evergreen forest

Basket makers

Arkadabooru

Pothos scandens

Climbers

Basket makers

B

Evergreen forest

Artisans







Stems of dead trees

Used as charcoal

L

Evergreen forest

Folk artists

Kiskara

Ixora coccinea

Flower

Coloring material

L

Scrubland/ Thickets

NTFP collector

Sheegakai

Acacia concinna

NTFP

Detergent

B

Scrubland/ Thickets

NTFP collector

Soapnut

Sapindus laurifolium

NTFP

Detergent

B

Scrubland/ Thickets

Artisans/ carpenters

Cashew (tree)

Anacardium occidentale

Wood

Implements

L

Scrubland/ Thickets

Artisans/ carpenters

Korajji

Ixora brachiata

Wood

Implements

L




LSE

UG

COMMON NAME

SCIENTIFIC NAME

CATEGORY

USE

M/L/B

Scrubland/ Thickets

Artisans/ carpenters

Matthi

Terminalia paniculata

Wood

Implements

L

Government plantations

Basket makers

Cane

Calamus sp.




Basket making

B

Government plantations

Firewood collector

Cashew

(branches)



Anacardium occidentale

Firewood

Fuel

L

Government plantations

Firewood collector

Acacia

(branches)



Acacia auriculiformes

Firewood

Fuel

L

Government plantations

Firewood collector

Teak

(branches)



Tectona grandis

Firewood

Fuel

L

Government plantations

Firewood collector

Casuarina

(branches)






Firewood

Fuel

L

Government plantations

Forest Dept officials

Acacia

Acacia aurifuliformes

Wood

Sale by auction

M

Government plantations

Forest Dept officials

Casuarina

Casuarina equiserifolia

Wood

Sale by auction

M

Government plantations

Forest Dept officials

Teak

Tectona grandis

Wood

Sale by auction

M

Value-added products based on ecosystem goods derived from forests used by outsiders include mats, baskets and rain-covers.


L = Locally used, M = Marketed , B = Both locally used and marketed, LSE =Landscape element category ( use based ), UG = User group

Ecosystem services:

Evergreen forests are origin of streams

Evergreen forests are repository of honeybees

Evergreen forest are of aesthetic and cultural value, especially at sacred spots, such as Brahmasthanam in Mala village.



Ecosystem bads:

( All the bads refer to evergreen forest )





Common name

UG

Dis-use

Wild Boar

Agriculturist / Plantation owner

Nuisance

Sloth Bear

Agriculturist / Plantation owner

Nuisance

Civet

Agriculturist / Plantation owner

Nuisance

Rat

Agriculturist / Plantation owner

Nuisance

Porcupine

Agriculturist / Plantation owner

Nuisance

Hare

Agriculturist / Plantation owner

Nuisance

Gaur

Agriculturist / Plantation owner

Nuisance

Bonnet macaque

Agriculturist / Plantation owner

Nuisance

Mite

Agriculturist / Plantation owner

Crop pest

Caterpillar

Agriculturist / Plantation owner

Crop pest

Stem borer

Agriculturist / Plantation owner

Crop pest

Terminal leaf eater

Agriculturist / Plantation owner

Crop pest

Tree borer

Agriculturist / Plantation owner

Crop pest

Beetle

Agriculturist / Plantation owner

Crop pest

Jungle fowl

Agriculturist / Plantation owner

Crop pest

Pea fowl

Agriculturist / Plantation owner

Crop pest

Quail / Patridge

Agriculturist / Plantation owner

Crop pest

Ticks

All UGs

Nuisance

Leeches

All UGs

Nuisance


Ecosystem disservices :
Evergreen forests are repositories of nuisance species, pests and vectors ( See above ).

9.2 Joint Field Visits

Information in official records of the harvest from forests, as well as management regime is often incomplete and inaccurate. Moreover such records are not readily accessible. Forest produce harvests, an important component of ecosystem goods and services are therefore best estimated through joint field visits with local people many of whom either work as forest labourers or collect forest produce for self-consumption as well as sale. The joint field visits may also be used to reconstruct the history of vegetation and of flow of ecosystem goods/ services/ bads/ disservices from particular forest patches.


9.3 Discussions

9.3.1 Discussions have produced a wealth of information on flows of ecosystem goods/ services/ bads/ disservices from the forest ecotopes. A significant historical event in this context was the large scale felling of trees for railway sleepers in mid 1960’s. An important species being so felled was Poeciloneuron, whose resin renders it susceptible to fire. Apparently there was a major crown fire during this operation leading to large scale death of forest tree populations and drastically changing the forest composition. A tribal hamlet in upper forest reaches reports, that it has required many decades after this fire for the streams to their locality to resume normal dry season flows.
9.3.2 A second major event reported was the commercial exploitation of canes (rattan) around the same time. Cane of several Calamus species had traditionally been very abundant in this forest and extensively used locally. It was marketed to a limited extent as baskets woven by some artisanal households. In particular cane harvests during 1960s included harvests of the top portion of rhizome along with the basal segment of the stem to produce walking sticks with hooked tops. This new practice reportedly totally decimated the very abundant cane stocks. However, in a recent welcome development the forest department has reintroduced cane species in several places within the newly declared national park.
9.3.3 This phase of exploitation and opening up of the canopy coincided with the invasion of the exotic composite weed Eupatorium odoratum (=Chromolaena odorata). This weed has profoundly affected the understory herbs and shrubs as well as trees regeneration and eliminated the sources of many minor forest produce as well as grazing for cattle.
9.3.4 These discussions also bring out that people have a basic appreciation of the idea that harvests from forests beyond a limit would lead to drastic depletions in the forest stock. They also understand successional processes, remarking that reduction of grazing and fire on grasslands enclosed by forest have led to a progressive change in the vegetation from grassland to shrubby growth to woodland.
10. FORESTRY PLANTATIONS

10.1 Measurements

Soil, water, biomass, harvests and biodiversity would be quantitatively assessed in case of the forestry plantations such as Casuarina equisetifolia, and Acacia auriculiformis following methods similar to these discussed for forests above.


10.2 Joint Field Visits

These are very useful in recording the history of forestry plantations, especially in terms of flow of ecosystem goods/ services – bads/ disservices from these locales. These exotic species plantations do not permit any undergrowth and thereby exclude grazing. They do not provide any leafy matter useful as green manure. Local communities therefore view these as responsible for substantial loss of ecosystem goods/ services earlier accessible to them.


10.3 Discussion

Forestry plantations have largely come up on lands that were earlier maintained as community grazing lands. During the period 1970s, there was a spurt of encroachment on these lands for cultivation and habitation both by the local inhabitants and immigrants. One of the official reactions was the handover of authority over such lands to Forest Department which brought them under plantations of exotic species which would resist grazing pressure.


11. GRASSLANDS

All the grasslands under the temperature, rainfall, soil conditions prevalent at Mala cluster study site are secondary, created either as a result of (a) shifting cultivation practiced earlier and discontinued around the end of the 19th century; these occur on upper hill slopes, or (b) deliberate clearance of forest around settled cultivation and habitation in the valley or lower hill slopes to create grazing resources for the cattle.


11.1 Measurements

Soil and water related measurements are to be carried out by appropriate methods as discussed earlier. Biomass may be estimated at the end of the growing season, coincident with cessation of rains around November through harvest of 1m x 1m sampling plots distributed randomly in a representative set of grassland patches. Biodiversity will be estimated through methods discussed further in section 14.


11.2 Joint Field Visits

Joint visits provide inputs on histories of particular grasslands and the flows of ecosystems goods/ services and bads/ disservices.


Table 14. Ecosystem goods/ services/ bads/ disservices associated with grasslands of Mala study cluster


LSE

UG

CATEGORY

USE

COMMON NAME

M/L/B

Grassland

NTFP collector

NTFP

Pickles

Emblica

L

Grassland

Animal husbandry

Grass

Fodder




L

L = Locally used

LSE = Landscape element category ( use based )

UG = User group



11.3 Discussions

People identify grasslands as an ecotype tope that has been especially eroded in recent decades, and whose ecosystem goods and services are now in great scarcity. This is traced to two causes: (a) rapid decimation of common property resources as traditional community organization and practices have changed due to a variety of forces of modernization, and (b) antipathy of forest authorities towards cattle and fire; two agents responsible for maintenance of grasslands.


12. DOMESTIC ANIMALS

Cattle, dogs and chicken are the three species maintained under domestication by a significant proportion of people since many generations. Buffalo, goat and pig have been introduced in the last few decades.


12.1 Measurements

Survey of randomly selected households from the different groups of people can provide estimates of biomass, productivity and the variety of goods and services furnished by domestic animals. There are no definable land races amongst the traditionally maintained domesticated animal populations. Therefore, while their range of variability may be noted, no investigation of land race diversity is called for.


12.2 Joint Field Visits

History of change in holding of domestic animals, availability of food resources to these animals, change in their productivity, diseases, predation by wild animals and the various goods and services provided by them can be ascertained through discussions involving visits to households and grazing lands. These also bring out some special insights: modern breeds of chicken are purchased only for meat and never maintained for any length of time since all chicken are kept as free range chicken feeding on their own. Moreover, cockfights are a favourite pastime and traditional chicken are selectively bred as fighting cocks. People talk of a pale mutant form of cattle “Kabetis” as a special sacred breed; in fact these appear not to be true breed, nor are there any attempts to deliberately breed for them.



12.3 Discussions

Free grazing cattle, primarily serving to convert natural vegetation into manure for agriculture was traditionally a significant link between natural and managed ecosystems. This link is now under considerable stress due to encroachment of common grazing grounds and deterioration of grazing resources in the forest because of the invasion by Eupatorium.


13. FISH

The aquatic ecosystems of Mala are primarily hill streams and some small artificial tanks and wells. Fish are neither especially abundant nor diverse in these waterbodies, yet they have been significantly depleted.


13.1 Measurements

Fish populations may be sampled using hook and line, cast nets, gill nets, baited traps or sweeps of rectangular nets. They may also be sampled in conjunction with fishing by people for their own purpose.


13.2 Joint Field Visits

History of changes in fish fauna in particular water bodies and forces driving these changes are well documented through joint visits. Also of relevance was the visit to a stretch of river protected through personal effort by a farmer who owns neighbouring lands.


13.3 Discussions

Discussions have led to many insights into the history of fish populations. Large scale road construction activity taken up in 1970’s has led to ready availability of dynamite. This has been used in destructive fishing leading to a serious depletion in fish populations, now estimated to be around 25% of the earlier level.




14. BIODIVERSITY

Biodiversity is an issue somewhat different from water, agriculture, forest, livestock or fish. While specific components of biodiversity are significant as sources of ecosystem goods/ services – bads/ disservices, biodiversity per se does not constitute such goods or services. Nevertheless status and trends in biodiversity per se are of substantial interest. But nobody has so far succeeded in carrying out an all taxa biodiversity inventory, let alone go down to the yet lower level of genetic diversity except to a very limited extent. So the measurement of biodiversity will have to focus on some specific components alone. For logistic reasons, we suggest the following upto species level: (a) angiosperms (b) butterflies (c) birds (d) fishes (e) molluscs. At the family level: (f) aquatic insects. At the level of varieties, cultivars, land races, we suggest (a) cultivated plants (b) domestic animals.


14.1 Measurement

14.1.1 For local level assessments it is sufficient to record presence/ absence without attempting to estimate abundances. The spatial units for the measurements should be individual elements within the landscape e.g. a forest patch, rubber plantation or a stretch of a stream. The attempt would then be to come up with a checklist of occurrence of relevant family/ species/ cultivar within the patch.
14.1.2 For this purpose we need some standardized methodology. A species list generated from an all out search of an area is the most frequently used method to survey the species diversity. However, a practical problem associated with all such efforts is the lack of knowledge of the number of species which are present but have been “missed”. Can one estimate the number of species which have been “missed” in this effort? An answer to this question will facilitate the evaluation of the “completeness” of the species list and hence the necessity for further sampling effort.
In an attempt to come up with a simple methodology to answer this question we undertook sampling exercises aimed at generating species lists for trees with three observers in four different habitats in Mala village. We present here the details of the sampling and data analysis methodology. The results of the analysis are also presented. Each of the 3 observers spent an equal amount of time (Tobs, in minutes) in each habitat while performing an all out search to prepare a list of observed species, spotting A, B and C sets of species respectively. Let Nobs be the cumulative number of species seen by the observers at the end of their sampling effort and Ntot be the total of number of species that are present in the area. The latter quantity needs to be estimated. Let Pi be the probability that the observer I will `spot’ a tree species. This quantity could also be understood as the efficiency of the observer. Now, the aim of the exercise described below is to estimate Ntot from the observed data. For the analysis the data is divided into the following seven categories:

  • Species seen by all three observers, A  B  C

  • Species seen by only two of the observers (A  B C, A  C B and B  C A)

  • Species seen by only one observer (A B C, B A C and C B A)


14.1.3 The values of these seven categories can be estimated as following:

  • Estimate of species seen by all three observers is, (p1p2p3)Ntot

  • Estimates of species seen by only two observers are: p1p2(1-p3)Ntot, p1p3(1-p2)Ntot and p2p3(1-p1)Ntot respectively.

  • Estimates of species seen by only one observer are: p1(1-p2)(1-p3)Ntot, p2(1-p1)(1-p3)Ntot and p3(1-p1)(1-p2)Ntot respectively.


14.1.4 We have four unknown parameters, p1,p2,p3 and Ntot to be estimated from seven data points estimates for which can be calculated as shown above. A 2 fit can now be performed on the data to extract the best estimates of these four unknown parameters. 2 is defined as 2 = (obsi-esti)2/ (esti) where, obsi is the observed value of any of the seven categories and esti is the associated estimate. The best estimates of these parameters are those that correspond to the minimum value of 2. A numerical procedure was implemented to minimize 2. The results of this analysis, indicating the best estimate of Ntot, for the four different habitat patches surveyed are presented below.





Evergreen

Scrub

Semi-evergreen(1)

Semi-evergreen (2)

2

9.58

6.96

4.18

11.08

Ntot(est)

76

58

108

86

Nobs

66

52

98

74

Tobs(in min)

90

60

170

80


Figure 8






Note: An estimator for Ntot should be independent of the sampling effort. The above figure (for data from semievergreen (1)) shows that except for very small sampling efforts our estimator for Ntot fulfills this requirement.
14.1.5 Using this methodology for the Mala study sites we have some preliminary data on flowering plants, butterflies, birds, aquatic insects and fish. Our interest is to interpret this data to obtain an understanding of how the biological communities are being impacted by ongoing interventions, and how to manage the interventions so as to do as well as we could from a biodiversity perspective. One possible approach to this is through assigning values to individual taxa, as well as assemblages from a conservation perspective. We quote below relevant portions of a study of birds of Western Ghats which attempts to do this (Pramod et al 1997).
14.2 Valuing Bird Taxa

14.2.1 We need to evaluate the bird species pools characterising the various habitat types. This is best based on an evaluation of the individual member species of the pool. This would be an exercise of quantifying the effort that the society might be willing to devote to ensure continued persistence of any given species. This would depend on a variety of attributes of the species. They belong to three major categories; rarity, extent of threat of extinction and utility. In general, rarer the species, the more threatened the species, the greater the utility of the species, the greater the effort that would be merited to ensure its continued persistence.
14.2.2 We may then assign to any particular species a conservation value reflecting this effort, such that the value would increase with rarity, extent of threat and utility. The actual values could either be ranks along a scale or a specific number. We propose to leave out attempts to quantify utility of bird species and assign quantitative values ranging between 0 and 1 on the basis of 7 attributes relating to rarity and extent of threat. Four of these values relate to the geographical range: G1, over the entire world divided into 6 zoogeographic regions; G2 over the oriental region divided into 9 subregions; G3 over the Indian subregion divided into 8 provinces; and G4 over the Malabar (Western Ghats plus West coast) province divided into 4 sections. The conservation value for a taxon by geographic range is given as:
G= (N-a)/ (N-1)
where `N’ is the number of subdivisions at a given level and `a’ is the number of subdivisions from which the taxon is known. This ensures that the more restricted the range on any of these scales, the greater would the conservation value be. The conservation value of each taxon by habitat preference was computed as :
H= (N-a) / (N-1)
where `N’, is the total number of bird habitat types over the Western Ghats region and `a’ the number of habitats favoured by a given taxon. This ensures that the more limited the habitat range of a species, the greater would the value be. The conservation value of a taxon reflecting its taxonomic distinctness was calculated as :
T= 1/(a * b)
where a is the number of species known in the family to which the taxon belongs and b is the number of races under the species. Rarity is thus sought to be captured in terms of narrowness of geographical range, narrowness of habitat preference and limitations on number of related taxa. The conservation value by degree of endangerment was assigned as:
E = p
where p is the proportion of endangered taxa in the family to which the taxon belongs. This methodology has been discussed earlier in some detail by Daniels et.al. (1991).


      1. Admittedly these attempts to capture rarity and endangerment in terms of

broad patterns of geographical distribution, habitat preferences, taxonomic position and number of related taxa recorded as threatened are crude. Nevertheless they are based on information which is available for all bird species of Western Ghats, indeed of the whole country, and therefore permit of an evaluation exercise which is reasonably objective and accessible for verification by all who may be interested. This overcomes problems which plague other more subjective exercises, including the listing of threatened species in IUCN sponsored red data books. Thus the peafowl (Pavo cristatus), the Nigiri Wood Pigeon (Columba eliphistonii), lesser adjutant stork (Leptoptilos javanicus) and the redfaced malkoha (Phaenicophaeus pyrrhocepahlus) are the 4 Western Ghats species included in the list of endangered species. However of these four the peafowl is widely distributed in India with many pockets of local abundance thanks to religious beliefs and the lesser adjutant stork is locally quite common in its appropriate habitat.
Distribution of Conservation Values

14.2.4 The 212 species encountered by us over the 132 transects are a subset of the 586 species of the Western Ghats. We have computed for the set of 586 species of Western Ghats conservation values for each of these 7 parameters, and a composite conservation value (CCV) as the sum of four values, namely the mean of the four values derived from geographical distribution and the other three values related to habitat preference, taxonomic uniqueness and degree of endangerment. This the CCV ranges between 0.66 for the Indian jungle crow, widespread, habitat generalist, a member of a speciose family with many races and of a family in little danger of extinction to 2.77 for crab plover, a wader with a restricted geographical distribution, narrow habitat preferences, and the only species in the family Dromadidae. The cumulative frequency distribution rises rapidly at either end, with about 520 species in the middle accounting for the values between 1.11 to 1.94. The bottom 22 and top 21 species with composite values substantially higher or lower than the majority are then of special interest. Fifteen out of these are birds of aquatic habitats, egrets, cormorants, cranes or skuas. Since our focus is on terrestrial habitats, we may take a closer look at the other species. The terrestrial species with highest conservation value include thrushes, babblers, woodpeckers, trogon, characteristic of forest habitats with narrow ranges at least at the subspecies level; and gallinaceous birds (quails, junglefowls etc.) that are extensively hunted and thereby threatened. The species with the lowest conservation values include passerines, swallows, hawks and falcons with a broad range of habitat tolerance and a wide geographical distribution, many of whom have adapted to human presence.
14.2.5 It is also of interest to examine the distribution of the composite conservation value amongst the broader groups of birds at family/subfamily level. Two groups of water birds herons and curlews, and one group of terrestrial birds hawks and vultures have significantly low composite conservation values. These have all very broad geographical distributions. Although the hawks and vultures have a significantly higher value in terms of endangerment, and curlews and sandpipers significantly higher value because of their more limited habitat preference, their CCVs are still significantly lower than the general population.
14.2.6 Three groups namely thrushes and chats, pheasants and quails and babblers and laughing thrushes have significantly higher CCVs. These they owe in all three cases to more restricted geographical distributions, and in the case of pheasants and quails also to significantly higher degree of endangerment. Three other groups of birds are notable for relatively high values along some of the dimensions of conservation value, though their CCV is not significantly higher. These include ducks and geese and pigeons and doves that have significantly high values in terms of endangerment, and woodpeckers that have significantly higher values in terms of restricted geographical distribution. Virakkala et al have suggested the use of woodpeckers as indicators of the health of forest habitats of Finland. For the terrestial habitats of Western Ghats the babblers would evidently be an appropriate choice as the group with the highest CCV.
Valuing habitats

14.2.7 Having thus quantified the conservation value at the species level, we can proceed to assign values to habitats on the basis of species they harbour. Most of the earlier exercises of this nature have primarily relied on species richness. An important advance in this context has been the use of taxonomic information as suggested Vane Wright and his co-workers. Our concept of mean composite conservation value is another attempt in this direction. It is notable that the two habitat types with lowest mean CCV, gardens and scrub savanna are also richest in the number of species whereas more natural habitats like shola-grassland and evergreen forest harbour comparatively lower number of rarer species which have a high conservation importance. This is because the former habitats are highly heterogeneous spatially and are colonised by a large number of opportunistic species with wide geographical distributions and broad habitat tolerances. It then appears appropriate not to base conservation decisions on simple species richness, strengthening the case for using a measure such as the mean composite conservation value. The mean CCV for shola-grassland is significantly higher than all other values, that of evergreen and semi-evergreen forests significantly higher than that of scrub- savanna and habitation,and that of deciduous forests significantly higher than that of gardens (all statistically significant at p < 0.05). The differences between evergreen forests, semi-evergreen or deciduous forests and monoculture tree plantations are not significant. A caveat is however in order here. All the localities surveyed by us are a highly intricate mosaic of several of these habitat types. In particular, the monoculture tree plantations surveyed are of small extent and tend to abut on patches of evergreen and, deciduous forests. Their bird communities though often poorer in total number of species, are made up of many elements from neighbouring forest habitats. This may be the reason why their mean CCV is not significantly lower in comparison with evergreen and deciduous forest types.

Exploring conservation values for ecotope types
14.2.8 Sixteen ecotope or landscape element types were identified in the Mala cluster. Fifteen of these were sampled for birds, butterflies and aquatic macroinvertebrates (Table 15). Representative patch of each landscape element type was visited between November 1999 and March 2000 to prepare a comprehensive checklist for birds, butterflies and aquatic macroinvertebrates. Both sighting records and indirect evidences (calls for birds) were used to prepare the checklists. Kick netting and all out search method were employed to sample aquatic macroinvertebrates.

Table 15. Ecotope Types of Mala cluster and taxa sampled.


Ecotope Type

Birds

Butterflies

Aquatic Macroinvertebrates

Evergreen

+

+




Semi evergreen

+

+




Riparian

+

+




Scrub

+

+




Thicket

+

+




Grassland

+

+




Paddy field

+

+




Casuarina plantation

+

+




Hopea plantation

+

+




Arecanut garden

+

+




Coconut grove

+

+




Cashew plantation

+

+




Rubber plantation

+

+




Acacia plantation

-

-




Human habitation

+

+




Streams







+
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