The goldcrest has much the same range and habitat preference as the common chiffchaff, and there is some evidence that high breeding densities of the kinglet depress the population of the warbler, although the converse is not true. There is no evidence that the species compete for territories, and in any case the chiffchaff is 50% heavier than the goldcrest. Nevertheless, there are 1.5 million breeding pairs of goldcrests in Finland, compared with 0.4 million breeding pairs of chiffchaffs, and only the kinglet has increased in numbers as the area of spruce woodland in the country has expanded. The goldcrest may be out-competing the warbler for food, especially as the larger bird faces more competition from other insectivores, including other "Phylloscopus" warblers. Both birds occur in similar forests, but the chiffchaff is found within of the forest edge, with the goldcrest breeding deeper in the woodland. Nevertheless, there is no conclusive evidence that the decline of the chiffchaff subspecies "Phylloscopus collybita abietinus" in parts of Finland is due to competition with the willow warbler and goldcrest.