Environmental Engineering Reference
In-Depth Information
(see the end of the chapter for links). These give exchange rates, inflation rates,
import and export figures, human population density, threat categories of
species, land cover and much more. It is worth remembering that official data
are not always reliable; however concrete they may look in the database, they
can, in fact, be very patchy. There is likely to be bias in data quality between
countries that could be correlated with the quantity you are interested in mea-
suring. For example, data quality on the number of threatened species in a coun-
try is likely to be worst in poorer countries, which are also the most biodiverse.
Aggregate figures are not always relevant to local situations. For example, in
large and disparate countries like Indonesia, local inflation rates can differ dra-
matically from the rates in the capital city.
●
Local government offices
are useful sources of relevant data that cannot be
remotely accessed. This might include unpublished reports, maps, local economic
statistics, data on conservation expenditures. Some of these data are likely to be
confidential or difficult to access.
●
Obviously there is a need to read all the relevant literature on a study site, includ-
ing
published accounts
of previous studies, and of studies in other areas that use
similar methods. However, in conservation and development there is often a lot
of
'grey
'
literature
—reports that are not published in recognised outlets, such as
consultancy reports and conference presentations. While web searches are
increasingly a fruitful way to find grey literature, to get a complete picture you
need to make personal contact with people who might have copies, or who know
the authors. This requires network-building through attending meetings, joining
newsgroups and approaching people with knowledge of the area.
●
There are also many creative sources of information. For example, explorers' tales
can be extremely useful in reconstructing patterns of abundance. Cornwallis
Harris (quoted in Martin and Martin 1982) recorded extremely abundant white
rhino populations in Cape region of South Africa in the 1830s, but only 70 years
later Selous (1908) was writing that over-hunting had led to the imminent extinc-
tion of the species. Pandolfi
et al
. (2001) used historical documents to show that
reef ecosystems had been fundamentally altered due to over-exploitation long
before current concerns about bleaching and disease developed. Caldecott (1988)
used official export records of illipe nuts from Sarawak as a proxy for mast fruit-
ing events in the region's Dipterocarp forests. He also used locally obtained
records of the products purchased by the Education Authority for children's
school meals as an indicator of wildlife abundance. He was able to show that tur-
tles were more often eaten at times of low water levels (when they were easier to
catch) and that bearded pigs were more often eaten during mast fruiting events
(when they became very abundant through migration and population growth).
The famous snowshoe hare cycle was deduced from nearly a century of records of
pelts lodged with the Hudson Bay Company (Maclulich 1937).
However useful they can be, these alternative information sources are limited,
potentially unreliable, and prone to bias and misinterpretation. The researcher
