In this photo the key field mark of the pale contrasting belly of sculpin in very clear. The head is under water, but the the body shape and fins are all arranged in formation to be one of the sculpin species that has a clear space on the penducle between the 2nd dorsal fin and the caudal (tail) fin. The fins are all erect and flared as the fish is very alive and struggling. These would start to collapse usually following death of the fish. Note the lateral line is conspicuous enough to see running low along the pale side. The pectoral fins are flared out and pink gills are viewable under the operculum. This is usually the only red color seen on sculpin as they don't bleed even when skin is ripped away (typically on the penducle). Fish size is probably 7-8 cm.
Monday, April 13, 2009
Pigeon Guillemot with a sculpin in British Columbia
Here is a Pigeon Guillemot with a sculpin in British Columbia which probably makes it Cepphus columba adianta which has on average a slightly smaller culmen (34 mm) than the guillemots of Oregon (35+ mm). Such a tiny difference is meaningless however in making field estimates of a couple cm. This sculpin is facing away from the viewer and is probably 6-7 cm long. Note the large pectoral fins and how the tail hangs down from the head. Sculpin held in this position (bill grabbing the sides) can appear floppy in the back end, whereas a dorsal-ventral hold they are a little stiffer bodied.
Pigeon Guillemot OregonCoast Canon
Given this photo was taken in Oregon late in the breeding season it is most likely Cepphus columba eureka, but the range between culmen length is not that great across the subspecies of Pigeon Guillemot and is reasonably estimated to be 35 mm. This fish is little more than 2 bill lengths or 7-8 cm. It is a great example of a sculpin, probably a Pacific Staghorn Sculpin, with the large head and rapidly tapering body. The sculpin is facing away from the viewer and the pectoral fins are the two things tapering away at 45 degree angles. These fins commonly are erected away from the body. If the fish were facing us it would have a bright white belly and often the mouth is agape. Scuplin often start producing slime that drips from the body if they are carried very long before consumption.
Elegant Tern (Thalasseus elegans) parent bringing a fish in her beak to her youngster
2 of 2 Elegant Tern (Thalasseus elegans) parent bringing a fish in her beak to her youngster, originally uploaded by mikebaird.
In this photo the anchovy is obviously a little larger than 2 bill length which would make the fish in the 12-14 cm size class. This anchovy also has a deepbody anchovy giss to it, but I am not certain without a better side profile that relates the anal fin and dorsal fin bases to each other (See Miller & Lea Fish Bulletin 157). The photograph was taken in Morro Bay which is in the northern range for the deepbody. Note how this picture shows little or no blood in contrast to the earlier photo. The big eyes, round nose, and small thin lower jaw leave no doubt that this an anchovy. The general flexibility here is also very typical.
Elegant Tern (Thalasseus elegans) parent bringing a fish in her beak to her youngster
1 of 2 Elegant Tern (Thalasseus elegans) parent bringing a fish in her beak to her youngster, originally uploaded by mikebaird.
This is a great shot of an anchovy, perhaps even a deepbody anchovy (Anchoa compressa) based on the relatively short distance between the back of the eye and the ventral edge of the operculum. Also the hues seem a bit more brownish green than the bluish black that is typical in the northern anchovy. The fact that the fish is bleeding and shows head wound trauma is very typical of anchovy in general. Elegant Tern bills range from 56 - 70 mm, but using a mean of around 63 mm would result in an estimated fish length of just over a bill and half or 10 cm.
Sunday, April 5, 2009
Caspian Tern with herring or sardine
This Caspian Tern has caught or repositioned this Clupeid and if you review the related Flickr photo set by jsutton8 you can see the tern evading some kleptopiratic Western Gulls. This fish is at least two bill length (7 cm) or approximately 15 cm. It has the small clear heavily forked and acuminate (pointy) tips to the tail and a sharp keel to the belly. Not the clear keel sharpness near the slightly flared operculum. An anchovy would be more rounded in the belly. The size and roundness of the operculum is chararcteristic of both herring and sardine in the SF Bay area and without a clear view of the mouth, head from the top and eyes it is impossible to tell.
Rhinoceros Auklet and a pair of Sand Lance
This breeding Rhinoceros Auklet is carrying a pair of Sand Lance which are relatively easy to identify because of their very skinny fusiform shape and the strong contrast between the dark back and bright silver belly. The tail fin appears to be under water but the caudal penduncle tapers symmetrically and very quickly which helps distinguish these fish from any other eel or lamprey. Sand Lance are very flexible and hang down from the bills regardless of the predator. If the exposed culmen is estimated at 32 mm then the fish must be 15 cm or 5 bill lengths.
