Esto, es uno de mis hobbys = This is one of my hobbies.
aquí, en la sombra de un árbol = here, in the shaddow of a tree
sentada en el canal = sitting at the channel
espero a que los cisnes pasen = I wait that swans are swimming by
o que los barcos con turistas pasen = or that boats with turists are coming by
porque los barcos con turistas sacan fotografías = the boats with turists take fotos
a todo lo que ven = what we see
y yo, si saludo = and I, if I greet
ellos me saludan de vuelta = they greet me back
has visto = have you seen
siempre saludan = they always greet