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Catorze anys d'estudis quiropterologics a les Illes Balears (1993-2006)



Les ratapinyades són mamífers euteris adaptats al vol que han tingut gran exit evolutiu i han  colonitzat  la  major  part  del  planeta  excepte  les  zones  polars.  Malgrat  la  seva importáncia ecológica, la distribució, l'ecologia i l a  dinamica de les poblacions de ratapinyades solen ser poc estudiades. El present treball dóna a coneixer i analitza l a  informació quiropterológica obtinguda des de 1993, any en que el nostre equip inicia els estudis a les IJIes Balears. S'han prospectat cavitats subterranies, s 'han capturat ratapinyades amb xarxes i s 'han efectuat enregistraments i analisis deIs senyals ultrasónics emesos pels quirópters pe r  tal d'ampliar la informació sobre la distribució de les ratapinyades a les Illes Balears. S'ha  analitzat l'ocupació estacional de Miniopterus schreibersii, Myotis  capaccinii,  Myotis  myotis  i Rhinolophus ferrumequinum  a 8  refugis  situats  a Mallorca i a Menorca  i s 'han estudiat desplayaments estacionals de les anteriors especies.  S 'han prospectat unes 400 localitats diferents i s 'ha  observat 16 especies de ratapinyades  a les Illes Balears, de  les  quals  algunes  d'elles han estat citades per primera vegada. Aquest és el cas de N.  leisleri a Menorca i Eivissa; P pygmaeus a Menorca i P pipistrellus,  P  kuhlii,  N.  leisleri,  M.  capaccinii,  B.  barbastellus  i  T.  teniotis  a  Sa Dragonera. Mallorca és l ' illa  amb major diversitat d'  especies de quiropters. Els resultats obtinguts fins ara, tot i que encara són parcial s, indiquen que existeixen diferencies en la composició de les comunitats de ratapinyades de  cada illa, j a  sigui en les especies presents  com en la freqüencia de  cadascuna d'elles. L'analisi de  l'ocupació estacional ha  mostrat la importancia quiropterologica de les cavitats estudiades i ha permes estimar el nombre  de  ratapinyades  que  s 'hi  refugien.  La  metodologia del marcatge-recaptura ha
possibilitat verificar diversos desplayaments entre cavitats. R. ferrumequinum i M.  myotis realitzen desplayaments de curta distancia, mentre que M. schreibersii i M.  capaccinii recorren distancies més llargues (tot i ser menors que  les observades  al  continent). S 'ha   pogut  comprovar,  per  primera  vegada,  desplayaments  de  M.  schreibersii  i  M. capaccinii entre colónies de Mallorca i Menorca.

SERRA-COBO, J. et al (2006)  Boll. Soc. Hist. Nat. Balears, 49

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