GVI.2014.1  

Female  infructescence  with  maturing  fruit  

 

Achievement  report  April  2014    

Report  Title  New  Coco  de  Mer  Survey  for  Curieuse  Island    

Summary  The   GVI   Seychelles   Terrestrial   Expedition   continues   to   develop   its   research   output   with   the  introduction  of  a  new  Coco  de  Mer  monitoring  protocol    

Report  As  of  May  2014,  the  GVI  Curieuse  programme  has  started  work  on  a  new  study  the  growth  rates  of  the   Curieuse   Island   Coco   de   Mer   population.   Working   closely   with   our   principle   partner,   the  Seychelles  National  Parks  Authority  (SNPA),  and  alongside  the  Seychelles  Island  Foundation  (SIF),  the  staff   and   volunteers   at   GVI   Curieuse  will   be   undertaking  weekly   hikes   deep   into   the   heart   of   the  island  to  conduct  various  measurements  on  75  specially  selected  Coco  de  Mer  trees.    The  Coco  de  Mer,  Lodoicea  maldivica  belongs   to   the   subfamily  Borassaidae  and   is  endemic   to   the  islands  of  Praslin  and  Curieuse  within  the  Seychelles.  There  are  three  distinct  populations  on  these  islands;   the  UNESCO  world  heritage   site   of  Valley   de  Mai   and   Fond   Ferdinand  on  Praslin,   and   the  Curieuse  Island  population.    

The  Coco  de  Mer  is  known  as  the  ‘Coconut  of  the  Sea’  and  is  infamous  for  its  distinctive  nuts.  Many  centuries  ago,  before  the  Seychelles  was  inhabited,  the  nuts  would  float  across  the  Indian  Ocean  and  gathered   from  beaches   in   the  Maldives   as   they  were   valued   as   an   important   trade   and  medicinal  item.  Legend  has  it  that  until  the  true  source  of  the  nut  was  discovered  it  was  believed  that  the  nut  originated  from  a  mythical  tree  at  the  bottom  of  the  sea.  European  nobles  in  the  sixteenth  century  would  often  have  the  shells  of  these  nuts  polished  and  decorated  with  valuable  jewels  as  collectibles  for  their  private  galleries.  

The   Coco   de  Mer   is   a   large   dioecious   palm,  with   the  male   and   female   flowers   found   on   separate   plants.  The   female   ‘inflorescence’  develops  between  3  and  5  lobed  fruits  which  can  weigh  up  to  20kg  and  contains  the  largest  seed  in  the  plant  kingdom.  It  takes  at  least  twenty   five   years   from   germination   for   the   palm   to  bear   fruit   and   the   fruits   take   approximately   seven  years  to  mature.    

 

 

   

GVI.2014.1  

Male  flowering  catkin  

The  male  Coco  de  Mer  palms  have  ‘catkins’  that  can  be   up   to   50cm   in   length.   They   bear   inflorescences  that   hold   numerous   yellow   flowers.   It   remains   a  mystery   how   the   pollen   from   the   male   catkins  pollinates   the   female   inflorescences,   however   a  report  from  the  SIF  team  in  Valley  de  Mai  is  due  out  very  soon  hopfully  sheding  light  on  the  matter.  

 

 For   the   survey,   the   Coco   de   Mer   trees   are  divided   into   ‘male’,   ‘female’   and   ‘juveniles’;  juvenile   are   then   subdivided   into   ‘seedling’,  ‘juvenile’   and   ‘immature’.   Seedlings   are   trees,  which   have   produced   three   or   fewer   leaves;  juveniles   have  more   than   three   leaves   but   no  trunk;   whilst   trees   with   a   trunk   but   no   sex  (neither   female   nor   male   inflorescences)   are  classed   as   immature.   Adults   are   Coco   de  Mer  trees  that  have  reached  a  reproductive  age  and  display  male  catkins  or  female  inflorescences.    

Thanks  to  the  hard  work  of  our  previous  volunteers,  we  already  have  a  list  of  75  trees  that  are  to  be  surveyed  every  3  months  as  part  of  the  new  Coco  de  Mer  growth  survey.  The  75  trees  are  made  up  of  15  from  each  classification  (male,  female,  seedling,  juvenile  and  immature)  and  are  found  along  a  transect  on  the  south  side  of  Mount  Curieuse.  All  trees  have  been  numbered  and  their  exact  position  recorded  with  a  GPS,  making  finding  them  a  little  easier.  Our  quarterly  measurements  will   include:  the   length   of   the   longest   leaf;   number   of   green   leaves;   diameter   of   trunk;   number   of   flowering  catkins  (for  males);  number  of  infructescences  and  nuts  (for  female);  and  length  of  trunk.  

Conducting  this  new  growth  survey  for  the  Coco  de  Mer  population  on  Curieuse  Island  will  provide  us  with  an  understanding  of  the  time  required  by  the  trees  develop  from  one  stage  to  the  next.    We  can   then  use   this  data   to  compare   the  populations   found  on  Curieuse   to   those   found  at  Valley  de  Mai   where   the   same   surveys   are   being   continually   undertaken.   As   the   Coco   de   Mer   found   on  Curieuse   show   particular   differences   to   the   populations   found   on   Praslin,   GVI   are   in   a   unique  position   to   provide   significant   scientific   insight   for   the   understudied   and   endemic   Coco   de   Mer  species.  

To  follow  our  progress  will  the  new  CdM  project  Follow  GVI  Curieuse  on  our  Facebook  page  GVI  SEYCHELLES  MAHE  &  CURIEUSE  and  follow  us  on  Twitter  @GVISeychelles    

     

   

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