Reef manta beam (Yards. alfredi) sightings and you will related hitchhiker species (1987–2019)
Spatial version on visibility really seem to observed hitchhiker species having M. alfredi (adult and you may teenager Elizabeth. naucrates) was indeed examined by mapping the fresh portion of sightings at each webpages (classified by site means) where in fact the hitchhiker species is establish (final amount of sightings in which hitchhikers had been noticed / final amount from sightings from the website) in ArcGIS ten.seven. People web sites with a total of 9 or fewer sightings (213 sites) were excluded to attenuate this new prejudice a low quantity of sightings might have toward study.
Temporary version throughout the presence of adult and teenager Elizabeth. naucrates that have Yards. alfredi try investigated using month-to-month day series. This show provided that time into the most useful amount of sightings (2008–2019) to include a suitable several months at which so you’re able to visualise trends (we.age., seasonality). This new monthly final number out-of sightings were corrected getting survey energy by calculating the newest suggest month-to-month amount of manta rays observed each questionnaire (month-to-month overall manta beam sightings / month-to-month final amount from studies).
Generalised linear mixed designs.
Logistic generalised linear mixed models (GLMM) using R v4.0.0 were used to investigate relationships between the presence of the most frequently observed hitchhiker species (adult and juvenile E. (more…)