(S (S (NP (BASENP (DT A) (JJ wet) (JJ late) (NNP Spring) (NN season) (POS 's)) (NP (BASENP (NN increase)) (PP (IN in) (BASENP (NN rainfall))))) (VP (VBD helped) (S (BASENP (NN duck) (NNS populations)) (VP (VB rebound) (PP (IN in) (NP (BASENP (DT the) (JJ northern) (NNP Great) (NNPS Plains)) (PP (IN near) (BASENP (DT the) (NNP U.S.-Canadian) (NN border))))))))) (PERIOD .))