SHORT COMMUNICATIONS 
181 
The Wilson Journal of Ornithology 123(1): 181-183, 2011 
Idle Lobster Traps Kill Blue Jays 
Mason H. Cline 1,3 and Joanna L. Hatt * 2 3 
ABSTRACT.—We report observations of Blue Jay 
(Cyanocitta cristata) mortality in idle lobster traps 
stored on Merepoint Neck in the Town of Brunswick, 
Maine. Three of nine individual Blue Jays found inside 
the traps were alive but emaciated. Each of the live Blue 
Jays was seen picking off and swallowing pieces of 
pectoral muscles from Blue Jay carcasses also inside the 
traps. We could not find literature describing or warning 
of the attractive nuisance posed to birds by improperly 
stored fishing gear, such as lobster traps. Our observa¬ 
tions identify a previously undocumented threat to local 
bird populations, and likely the first documentation of 
adult-adult cannibalism for the Blue Jay. We suggest 
some simple solutions to mitigate avian mortality due to 
improperly stored fishing gear. Received 22 June 2010. 
Accepted 9 October 2010. 
It is widely known that idle and derelict fishing 
gear cause unintended mortality to marine organ¬ 
isms (Macfadyen et al. 2009). However, we found 
no documentation describing the threat that idle 
fishing equipment poses to terrestrial organisms, 
such as passerine birds. Until this report, idle and 
improperly stored fishing gear has not been 
acknowledged as a real and serious threat to 
survival of terrestrial birds. We describe observa¬ 
tions of inadvertent trapping and subsequent 
mortality of a terrestrial songbird, the Blue Jay 
(Cyanocitta cristata ), in idle fishing equipment. 
We also document adult-adult cannibalism by 
Blue Jays. Reports of adult-adult cannibalism in 
wild birds are uncommon. Generally, in wild 
birds, cannibalistic behavior is thought to be the 
product of either extreme aggression or opportu¬ 
nistic nutritional exploitation (Stanback and 
Koenig 1992). Conversely, reports of captive 
birds exhibiting cannibalistic behavior are fairly 
common. Cannibalism by captive birds is often 
cited as the product of social and environmental 
stresses associated with captivity (Duncan and 
Hawkins 2010). 
'585 Butter Hill Road, Chatham, NH 03813, USA. 
2 164 Federal Street, Wiscasset, ME 04578, USA. 
3 Corresponding author; e-mail: mason.cline@gmail.com 
OBSERVATIONS 
Observations were made during a Christmas 
Bird Count on Merepoint Neck in the Town of 
Brunswick, Maine. On 3 January 2010 at 0930 hrs 
EST, while surveying for birds at a public boat 
launch near the southern terminus of Merepoint 
Neck, we noticed —80 metal lobster traps stacked 
in a rectangular formation. The lobster traps were 
on property adjacent to the public boat launch. 
Upon closer inspection, we detected three live 
Blue Jays caught in three separate lobster traps. 
The birds could enter the traps, but once inside 
they were unable to escape. The trapped Blue Jays 
were initially observed through binoculars from a 
distance of —50-75 m. During our initial 
observation, we noticed a number of Blue Jay 
carcasses within the lobster traps, in addition to 
the three live birds. Furthermore, the trapped Blue 
Jays were observed tearing off and swallowing 
flesh from the dead Blue Jays. 
We approached the traps to extract the live 
birds. Two of the live individuals had pieces of 
Blue Jay muscle tissue on their bills. In hand, all 
three live jays appeared to have reduced muscle 
mass and felt abnormally bony and light. Upon 
release, two jays flew strongly while one was 
noticeably weak and barely able to fly. After the 
live birds were freed, we carefully examined the 
six carcasses remaining in the traps. We noted the 
pectoral muscles of the carcasses were absent and 
there was no evidence of the missing muscle 
tissue in the traps or on the snow around or 
beneath the traps. 
Our direct observations of live birds swallow¬ 
ing conspecifics’ muscle tissue coupled with an 
absence of pectoral muscle tissue on the snow 
around the traps (which would have been clearly 
visible on the white background), provides 
unambiguous evidence for adult-adult cannibal¬ 
ism by the Blue Jay. Displacement behavior has 
been documented for Blue Jays (Jones and Kamil 
1973), but we did not observe this behavior. If 
displacement behavior had been occurring, we 
believe that plucked-off and discarded flesh 
would have been visible in or around the traps. 
