Please enable JavaScript.
Coggle requires JavaScript to display documents.
the pearl mussel / pearl mussels mussel-in-clean-pc_med_hr, Latin…
the pearl mussel / pearl mussels 
where ?
-
-
clear + UNpolluted water + salmoN + brown trouT - filtering water = good quality ! bath-sized quantity / day !
< 50 rivers in the world = worldwide (poor water quality) # all in Europe & Northern America (millenia ago)
-
accumulation of sediments => juveniles cannot survive = ageing population (ex UK youngest colonies = 30 y o
freshwater (rivers) - sand - fine gravels - cobbles (galets) - to span = to spread along / across river
-
(hi)story ? The Romans invaded GB in 55 BC for the pearl mussels / 19th c = big trade --> end of 19th = unsustainable --> NOW complete LEGAL protection = protected by LAW (since 1998)
bivalve - mollusc - shell (oval, black, corroded appearance - < 15 cm ) - pearly white body - filter to feed / for food (above = top) + foot (under = beneath) -
dangers
pearl (white / pinkISH) = in a small proportion of mussels (to take it = to kill the mussels) = danger for the species
-
-
-
-