Before the relative importance of any species can be judged in conservation terms, some form of evaluation is required. At present, the criteria generally used by conservation agencies and others to indicate important species are those of the Red Data Book programme, e.g. Branch (1988b). These criteria do not use numerical ratings but are generally based on subjective assessments. The Natal Parks Board uses a system (Bourquin, 1990) which has been devised to rate species importance in KwaZulu-Natal. This system, suitably modified here to cater for national ratings, is proposed for use in evaluating the conservation status of dwarf chameleon species.The scoring system used enables taxa or populations to be given a numerical conservation priority rating. These ratings are based on the following criteria :

(i) Habitat specificity

(ii) Distribution range in S Africa

(iii) Regional endemism

(iv) Relative presence

(v) Protection

(vi) Threats

This system gives high scores in cases where the conservation risks are high and low scores where there is little or no risk involved.

Although this system has obvious problems due to the subjectivity required in making some choices, it has proved useful for the Natal Parks Board in providing indications of species importance and establishing information requirements for each species or taxon (Bourquin, pers. comm. 1994). Where information is not available for species which are clearly rare, then recommendations for further research become apparent.

Restricted to a specific habitat type (e.g. cliff face, sand forest) 5

Restricted to a broad habitat type, excluding man-modified habitats 3

Restricted to a broad habitat type, including man-modified habitats 2

Able to survive in most natural habitats, excluding man-modified habitats 1

Able to survive in most natural habitats, including man-modified habitats 0

Localised in a larger portion (16-30%) of S Africa 3

Widespread but only found in localised small areas 2

Widespread over a major portion (>30%) of S Africa 1

Widespread over virtually whole of S Africa 0

(N.B. For the purposes of this document the 9 provinces of South Africa, together with the neighbouring countries Botswana, Lesotho, Mozambique, Namibia, Swaziland and Zimbabwe are all regarded as territories.)

Occurring in only 1 territory 5

Occurring in 2 territories 3

Occurring in 3 territories 2

Occurring in 4 territories 1

Occurring in 5 or more territories 0

(N.B. Grid cells referred to are 1/4E grid cells. Some 1850 cells cover S Africa)

Very rare - recorded from < 16 grid cells 5

Rare - recorded from 16 - 50 grid cells 3

Fairly common - recorded from 51 - 200 cells 2

Common - recorded from 201 - 500 grid cells 1

Very common - recorded from > 500 grid cells 0

Poor - recorded from 4 or fewer reserves 5

Restricted - recorded from 5 - 10 reserves 3

Fair - recorded from 11 - 20 reserves 2

Good - recorded from 21 - 30 reserves 1

Very good - recorded from more than 30 reserves 0

(N.B. Where the decline over the last 10 years, or the present number of individuals is unknown, then an estimate should be made which takes into account habitat loss, utilisation and other factors.)

Over 80% of the populations have declined or less than 500 individuals remain 5

60 - 80% of the populations have declined or between 500 and 1000 individuals remain 3

30 - 59% of the populations have declined or between 1000 and 2000 individuals remain 2

10 - 29% of the populations have declined or between 2000 and 5000 individuals remain 1

less than 10% of the populations have declined or more than 5000 individuals remain 0

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