Untitled - WWF - Pakistan

More documents

Recommendations

Info

Detailed Ecological Assessment Report 2008 – Keenjhar Lake Searching for the nocturnal species of amphibians and reptiles was carried out in exposed areas of their potential habitats on the ground, along the path or the pond/stream bank. Night survey in some of the rocky terrain around the Keenjhar Lake was difficult as there was always a likelihood of venomous snakes, as the author did face; so, long shoes, hand lamps and powerful torches were used for this purpose. 2.3.3 Signs Presence of signs like impression of body, tail or footprints, faecal pellets, tracks, dens or egg laying excavations, were also some of the suitable methods to find out the existence, range and rough population of amphibian and reptilian fauna. 2.3.4 Collection Hand picking (through bare hands or with the help of long forceps or snake clutch), adopted for the present studies, has always been the most efficient way of collecting different species of amphibians and reptiles. However, for larger species like monitor lizard and rock-agama, noose traps or other appropriate techniques were used. For handling snakes, especially poisonous ones, snake clutches/ sticks were used. In addition to Hand picking, “Scoop nets” for shallow water and “Cast nets” in large water bodies were used for aquatic reptiles and amphibians. For frogs and toads, auditory detection of mating calls at the breeding sites is considered as an efficient method to find out the species; particularly the more vocal species and therefore a large number of toads were spotted with this method. 2.3.5 Data records The species collected or observed during the survey were photographed with a digital camera and necessary field data were recorded. The coordinates and elevations were recorded with the help of GPS. The voucher specimens collected were subsequently transported to the Pakistan Museum of Natural History (PMNH) laboratory for future reference. 2.3.5 Preservation The amphibian or reptile specimens were arranged in a tray or ice-cream container in a position, which showed the features important for identification, e.g. mouth wedged open, one hind leg extended and fingers and toes spread. Preservatives such as 10 % formalin solution or 50-70 % alcohol or methylated spirits solution in water was added to just cover the specimens, and the container was then covered and left until the specimens were set. In case of larger specimens, a slit was made in the belly and preservative injected to preserve the internal organs. This step was omitted in case of frogs as they have thin and permeable skins, but in case of reptiles, the preservative was injected into their bodies as their skin is impermeable and does not allow any solution to get into. For this purpose normal syringes were used. The specimen was stored in the same preservative in a watertight jar. A waterproof label was added to the jar, giving details of place, date and collector’s name. A label was tied to the specimen written with permanent Indian ink or simple carbon pencil. The same details were stored with tadpole specimens, which don’t need to be set, just dropped into preservative. WWF Pakistan – Indus for All Programme Page 28 of 165
Detailed Ecological Assessment Report 2008 – Keenjhar Lake 2.3.6 Identification of species The specimens were identified with the help of most recent keys available in literature (Khan, 2003, 2006). 2.3.7 Data analysis There are several numerical indices in use, which quantitatively describe different levels of diversity and evenness in samples collected from different localities or at different times from the same environment. One such commonly used diversity index is called “Shannon-weaver” index of diversity, which combines the number of species present and evenness into a single index. The formula is given as: D = -Σ pi in pi where “i” stands for an index number for each species present in a sample, “pi” can be calculated through “ni/N” in which “ni” represents the number of individuals within a species divided by the total number of individuals “N” present in the entire sample and “ln” stands for natural log. In this way the proportion “pi” of each species in the sample times the natural log of that same value “ln pi” the values for each species and finally multiplied by –1. The value of “D” is always higher when species are equally abundant. Similarly species evenness is calculated by the formula as: E = eD/s, where “e” is the Shannonweaver constant valuing 2.7, “D” is the value of Shannon-weaver index and “s” represents the number of total species in a sample. Species evenness, thus, separates the effect of different population sizes (number of individuals within species) from number of species (species diversity). 2.4 Birds 2.4.1 Survey method Each major habitat type in the study area was identified and records were kept of species of birds found in each discreet habitat such as lakes, canals, ponds, marshes, coastal areas, creeks, forest, agriculture fields, mangrove areas, vicinity of human habitation and fallow lands. The number of birds observed in each habitat type was also recorded with particular emphasis on the key species and to relate the data to other components of the study area such as vegetation, water and soil etc. The most commonly used field method in bird surveying is the “Line Transects” method. It is based on recording birds continually along a predefined route within a predefined survey unit. It can be used in terrestrial, freshwater, and marine systems to survey individual species, or group of species. It is used to examine bird-habitat relationships and to derive relative and absolute measures of bird abundance. Line Transects are suitable for extensive, open and uniform habitats and for large and conspicuous species. Double counting of birds becomes a minor issue as the observer is continually on the move. Line Transects are suited to situations where access is good and these are very useful for bird-habitat studies (Gregory et al 2004). In the present studies, each sample area was transversed / examined by 2 observers, separately. Birds were searched on each side of the strip for 150m so that each study strip was 300m wide. Use of binoculars and telescopes was made to identify bird species, count or assess bird numbers, particularly in case of water-birds. WWF Pakistan – Indus for All Programme Page 29 of 165
Page 2 and 3: Disclaimer note This information sh
Page 4 and 5: Detailed Ecological Assessment Repo
Page 8 and 9: List of tables Detailed Ecological
Page 78 and 79: 29 30 31 32 33 34 35 36 37 38 39 40
Page 98 and 99:
Detailed Ecological Assessment Repo
Page 100 and 101:
Page 102 and 103:
Page 104 and 105:
Page 106 and 107:
Page 108 and 109:
Page 110 and 111:
Page 112 and 113:
Page 114 and 115:
Page 116 and 117:
Page 118 and 119:
Page 120 and 121:
Page 122 and 123:
Page 124 and 125:
Page 126 and 127:
Page 128 and 129:
Page 130 and 131:
S. No. Detailed Ecological Assessme
Page 132 and 133:
Page 134 and 135:
Page 136 and 137:
Page 138 and 139:
Page 140 and 141:
Page 142 and 143:
Index value Detailed Ecological Ass
Page 144 and 145:
Index value Detailed Ecological Ass
Page 146 and 147:
Page 148 and 149:
Page 150 and 151:
Page 152 and 153:
Page 154 and 155:
Page 156 and 157:
Page 158 and 159:
Detailed Ecological Assessment Stud
Page 160 and 161:
Page 162 and 163:
Page 164 and 165:
Page 166 and 167:
Page 168 and 169:
Page 170 and 171:
Page 172 and 173:
Page 174 and 175:
Page 176 and 177:
Page 178 and 179:
Page 180 and 181:
Page 182 and 183:
Page 184 and 185:
show all

Untitled - WWF - Pakistan

Create successful ePaper yourself

Delete template?

Save as template?