Atlantic Puffins Fratercula Arctica Research Articles

Chick Growth, Fledging Periods and Adult Mass Loss of Atlantic Puffins Fratercula arctica during Years of Prolonged Food Stress

Chick Growth, Fledging Periods and Adult Mass Loss of Atlantic Puffins Fratercula arctica during Years of Prolonged Food Stress

Energy Metabolism in the Locomotor Muscles of the Common Murre (Uria aalge) and the Atlantic Puffin (Fratercula arctica)

Abstract To compare the metabolic systems that support the combination of flying and diving with those used to support burst flying and sustained flying, myoglobin concentrations and maximum enzyme activities were determined for selected enzymes of glycolysis, the Krebs cycle, and amino acid metabolism in the pectoral, supracoracoideus, and sartorius muscles of the Common Murre (Uria aalge), Atlantic Puffin (Fratercula arctica), Rock Dove (Columba livia; hereafter "pigeon"), and Ring-necked Pheasant (Phasianus colchicus). Glycolytic enzyme levels in the flight muscles were lower in the murre and the puffin than in the pheasant, while both glycolytic and Krebs-cycle enzyme levels resembled those in the pigeon. We believe puffins and murres do not rely extensively on anaerobic glycolysis during diving. In concordance with a role in oxygen storage for diving, the levels of myoglobin in the flight muscles of murres and puffins were higher than those in pigeons or pheasants. They were lower than published values for penguins, however. In contrast to the trends for pigeon and pheasant muscles, the alcid sartorius muscles had a considerably lower aerobic orientation than the flight muscles.

Scale-dependent correlation of seabirds with schooling fish in a coastal ecosystem

The distribution of piscivorous seabirds relative to schooling f ~ s h was investigated by repeated censusing of 2 intersecting transects in the Avalon Channel, w h c h carries the Labrador Current southward along the east coast of Newfoundland. Murres (primarily common murres Uria aalge), Atlantic puffins Fratercula arctica, and schooling fish (primarily capelin .Mallofus villosus) were highly aggregated at spatial scales ranging from 0.25 to 15 km. Patchiness of murres, puffins and schoohng flsh was scale-dependent, as indicated by significantly higher vc~ridnce-to-mean ratios at large measurement distances than at the minimum distance, 0.25 km Patch scale of puffins ranged from 2.5 to 15 km, of murres from 3 to 8.75 km, and of schoohng flsh from 1.25 CO 15 km. Patch scale of birds and schooling fish was sirmlar m 6 out of 9 con~parisons. Correlahon between seabirds and schooling birds was significant at the minimum measurement distance in b D L I ~ of 12 comparisons. Correlation was scale-dependent, as inlcated by sigruficantly higher coef1i:ients at large measurement &stances than at the minimum distance. Traclung scale, as indicated b) Lhe maxlmum significant correlation between birds and schooling fish, ranged from 2 to 6 km. Our analysis showed that extended aggregations of seabirds are associated with extended aggregatlons of schooling fish and that correlation of these marine carnivores with their prey is scale-dependent.