UnScramble this Word: o g e r d d?

Questions

what was the name of the dolphin who, for more than two decades, guided steamships through perilous waters into safe harbour off new zealand?

what was the name of the horse who reputedly could do arithmetic?

a carrier pigeon who served in wwi, who stopped an american bombardment of american troops, cher ami, is now on permanant display where?

famous dog who starred in 'where the north begins', 'clash of the wolves' and 'dogs of the regiment'.?

who was the first animalnaut?