Porcupine population fluctuations in past centuries revealed by dendrochronology.
Describes a survey of porcupine feeding on Pinyon and Yellow Pine in the Mesa Verde area (S.W. Colorado). A tree-ring chronology was constructed, based on the mean annual growth of 10 trees selected at random; actual records of recent porcupine numbers and damage were compiled; and some 2000 feeding scars were dated by microscopic examination of sections. Results showed that in the last 120 years four population eruptions occurred, numbers reaching peaks in 1845, 1885, 1905 and 1935. Earlier population eruptions at ca. 1716, 1745, 1785 and 1815 are also suggested. KEYWORDS: Animal damage \ Dendrochronology dating \ fluctuations \ porcupine populations \ mammals \ vertebrate pests \ Pinus edulis \ Pinus ponderosa injury \ porcupine \ Porcupines \ protection \ forests \ Rodents \ Skidding wheeled skidders