SUMMARY OF THE PROJECT ENTITLED
“TOURISM INDUCED CHANGES IN THE MEIOFAUNAL DIVERSITY OF CHERAI
BEACH – A PROMINENT TOURIST BEACH OF KERALA”
By
Dr. Priyalakshmi G
Dept. of Zoology
Bharata Mata College
Thrikkakara, Kochi
The world’s sandy beaches are iconic assets to society, but escalating threats to
these systems pose formidable conservation challenges. During the last decades,
recreational activities have been increasing rapidly as people enjoy more leisure time
and higher standards of living. Many of these activities are focused on coastal tourism.
Tourism has long been considered as a clean industry with almost no negative effects
on the environment. Partly due to their barren appearance, sandy beaches have not
been regarded as vulnerable to human disturbance (Poulson & Mc Clung, 1999). But
beaches are not just piles of sand; they support a range of underappreciated
biodiversity. Sandy beaches harbour diverse and abundant assemblage of marine
organisms. Besides macrofauna, the sandy beaches are profusely inhabited by
microscopic organisms belonging to the lower and higher invertebrate taxa. These
organisms that occupy the spaces between the sand grains are called ‘Interstitial
Fauna’ or ‘meiofauna’. The diversity of these interstitial organisms that inhabit the
interstices of beach sands in the intertidal realm is so astounding that 22 of the known
33 metazoan phyla have their representatives living in this ecosystem. The
Gastrotricha, Kinorhyncha, Gnathostomulida, Loricifera, Mystacocarida, Nematoda,
Polychaeta, Copepoda, Ostracoda, Turbellaria, Halacaroidea, Hydrozoa, Nemertina,
Entoprocta,
Gastropoda,
Aplacophora,
Brachiopoda,
Holothuroidea,
Tunicata,
Priapulida, Sipuncula and many representatives of Rotifera are permanent meiofauna,
whereas some organisms like the larvae of macrofauna are a part of meiobenthos, only
during their juvenile stages (temporary meiofauna).Thus, benthos represents a major
component of the marine environment and plays a vital role in the overall food chain in
the sea (Ganesh & Raman, 2007).
The impact of tourism does not only include the human trampling on the beach itself,
but the whole of activities to maintain it, such as mechanical beach cleaning. Physical
disturbance by cleaning activities is already known to cause a decrease or
disappearance of macrofauna (Brown & Mc Lachlan, 1990; Mann, 2000). Their effects
on the interstitial meiofauna are unclear (Gheskiere et al., 2005). From an Indian
perspective, the impact of tourism on the abundance and diversity of meiofauna is an
area that still remains almost untouched. India is losing at an alarming rate its vast
genetic heritage, the animal wealth of the country, even before these are properly
studied and understood. It has become absolutely essential to obtain information on the
identity, distribution, interactions and population levels of animal species so that the
future developmental programmes (like Tourism) should not be at the cost of our faunal
wealth. A better knowledge would draw the attention of a wider scientific public to
meiobenthos not only as a scientifically most rewarding animal group, but also as an
exemplary and convenient scientific tool to assess pollution. The project on ‘
Tourism induced changes in the meiofaunal diversity of Cherai beach-a
prominent tourist beach of Kerala’ was done to achieve the following objectives such as

Enumeration of the numerical abundance of aberrant groups of meiofauna of
Cherai beach.

To study the species diversity of the interstitial fauna.

To make an inquiry into the related ecology.

To make a comparison of the meiofaunal density and diversity of Cherai beach2005, then a pristine beach with the meiofaunal diversity of present day Cherai
beach- now a prominent tourist spot of Kerala.
Cherai beach (lat.1009 N; long.7602 E), the area of study is a 15 km long stretch,
located 30 km north of Kochi with gentle slope and moderate wave action. The sampling
stations include the main tourist spot (considered as a polluted region) as Site 1 and Site 2
is located 1.5 Km away from site 1. Cherai beach, now a prominent tourist beach was a
pristine beach at the beginning of this century. Bimonthly collections (Aug-Sept; Oct-Nov;
Dec-Jan; Feb-Mar; April-May; June-July) and observations were done during the low tide
for a period of one year (2011-12). Using all standard protocols, sediment texture and
density and diversity of interstitial taxa of sediment samples were worked out and analysed.
Statistical analysis using Primer version VI was also done.
The sediments at Cherai beach were well sorted or moderately well sorted. More than 50%
of the sand fraction was medium sized in all seasons of the year. According to Giere
(2009), moderately well sorted medium sand harbours the most diverse meiofauna. Eleven
meiofauna groups were recorded during the present study. Nematodes generally constitute
the dominant taxa in any habitat. Though nematodes were invarianly present at both
stations in different seasons of the year, they did not constitute more than 25% at any of
the locations in the present study. Reduction in the meiofaunal density of nematodes at
Cherai beach in the present study is surprising. The presence of sensitive or tolerant
meiofaunal taxa and nematode genera appears to be particularly informative in
highlighting the state of sediment pollution and allows a better assessment of the spatial
heterogeneity of environmental disturbance (Moreno et al., 2008).The current
investigation revealed the occupancy of gastrotrichs at the dominant position in Cherai
followed by turbellarians.
Tourism cannot be blamed as a sole factor that can lead to a diminution of meiofaunal
taxa since majority of interstitial taxa are well represented in Cherai in the current study
even during the monsoon. A comparison of bimonthly collection of total meiofaunal
density at station 1 and station 2 proves beyond doubt that unpolluted regions have a
better chance of survival for meiofauna than an area which is frequented by tourists
from India and abroad
A comparison of the meiofaunal density and diversity of Cherai beach, based on studies
conducted in 2005-06 and 2011-12 revealed several interesting features. Tourism
cannot be taken as a causative factor which can diminish meiofaunal diversity since
meiofauna belonging to eleven taxa were represented in the present study in contrast to
nine taxa observed in the previous study. The major groups of organisms were found in
almost all seasons of the year. But nematofauna, which dominated in the samples
collected from Cherai in 2005-06, is outnumbered by Gastrotricha, an aberrant group of
meiofaunal organisms. The community structure of nematodes seems to have changed
over a period of time where, Rhynchonema and Metepsilonema found in very few
numbers in 2005-06 was seen in plenty in the present collection. A general reduction in
the density and diversity of nematodes was noticed. Whether their absence during AprilMay is an impact of climate change or due to the influx of tourists during the summer break
is yet to be ascertained.
Gastrotrichs were totally absent in Cherai during the monsoon in the
previous study whereas, they were well represented in the current study and a marked
reduction of these organisms was noticed in April-May. Untimely showers in summer
coupled with the absence of proper monsoon in 2011-12 could have led to this
unprecedented situation. Several genera found in abundance in the study conducted in
2005-06 is found missing now. Saccocirrus minor, an interstitial polychaete is a classic
example for this. Gnathostomulids and foraminiferans are new arrivals in the present
study and the disappearance of Cnidaria and Isopoda are conspicuous. Comparison of
faunal diversity and density of Cherai in 2005-06 and 2011-12 leads to the conclusion
that tourist activities without extensive construction and dredging cannot have a marked
effect on the density and diversity of meiofauna, but when coupled with industrial
pollution or extensive mechanical beach cleaning activities, can have a negative impact
on the interstitial organisms. A change that has occurred in the community structure of
interstial organisms over a period of six years cannot be overlooked. The use of modern
molecular
biology
techniques
to
assess
genetic
diversity
of
meiofauna
in
contaminated vs uncontaminated sediments is a promising avenue for future research.