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Mormon Island; HARLAN CO. (17): Republican
River S of Orleans; HOLT CO. (1):
Spencer; HOOKER CO. (1): Mullen; JEF-
FERSON CO. (16): No data; JOHNSON CO.
(75): No data; KEITH CO. (61): Cedar Point
Biological Station; KEYA PAHA CO. (7):
Mills, Norden; KNOX CO. (45): Bazile Creek
Wildlife Management Area; LANCASTER
CO. (64): Lincoln, Reller Prairie, Sprague;
LINCOLN CO. (1,142): Brady, Box Elder
Canyon, Cottonwood Canyon, Moran Canyon,
North Platte, 2 mi. S Sutherland, Wellfleet;
McPHERSON CO. (1): No data; NUCK-
OLLS CO. (1): No data; OTOE CO. (476):
Nebraska City; PAWNEE CO. (706): No
data; PHELPS CO. (27): Bertrand; PLATTE
CO. (2): Columbus; RICHARDSON CO. (2):
Indian Cave State Park; SALINE CO. (431):
Swan Creek; SARPY CO. (612): Fontenelle
Forest, Schramm Park; SAUNDERS CO.
(680): Mead, Wahoo; SIOUX CO. (35): Gilbert
Baker Wildlife area, Monroe Canyon;
THOMAS CO. (165): Halsey Forest Reserve;
WASHINGTON CO. (629): Ft. Calhoun.
Temporal Distribution. Rangewide:
February to October (Peck and Kaulbars
1987). Nebraska: May (58), June (432), July
(2,349), August (5,188), September (597),
October (214).
Remarks. Nicrophorus orbicollis is the
most abundant and commonly encountered
species of Nicrophorus in the state. The long,
elytral setae are diagnostic for this species,
but they are occasionally abraided away and
so caution should be used when identifying
specimens. It most closely resembles N.
mexicanus, but N. mexicanus has a bicolored
epipleuron whereas N. orbicollis has a black
epipleuron.
The larval stage was described by
Anderson (1982), and a brief larval diagnosis
was provided by Anderson and Peck
(1985).
Shubeck (1984a, 1993) and Lomolino
et al. (1995), in studies in New Jersey, Oklahoma
and Arkansas, demonstrated that this
species seems to show a preference for for-
THE CARRION BEETLES OF NEBRASKA 79
ested areas. Contrary to these studies, this
species is found abundantly in the grasslands
of western Nebraska as well as the forested
areas of eastern Nebraska. Lingafelter (1995)
observed a similar pattern in Kansas. Nicrophorus
orbicollis is the most commonly collected
species in eastern North America (Peck
and Kaulbars 1987) and seems to be the most
abundant species of Nicrophorus in Nebraska.
Trumbo (1990d) reported that they are the
dominant burying beetle on small carcasses
in the woodlands of the eastern United States.
Shubeck (1971) reported they are nocturnal
and are often taken at light traps; this has
been my experience also.
Adults overwinter and become active in
the spring at which time reproduction takes
place. Nicrophorus orbicollis is successful on
a higher proportion of carcasses of all sizes
and gains substantial benefits by excluding
rivals; it rarely tolerates consexuals in the
nest (Trumbo 1995). Generally, the male
parent remains in the nest 5-12 days and
the female parent for 10-15 days (Scott and
Traniello 1990b, Trumbo 1991). In another
study (under natural conditions in the field),
Scott (1990) found that N. orbicollis males
remained with the brood a mean of 9.5 days
and females 17.2 days; however, 22% of the
broods were reared by single females. In
her experiments examining male assistance
in guarding against conspecifics, 87% of
the males and 93% of the females were still
present after eight days; females normally
remain with the brood longer than eight days
post-burial. This long period of parental care
represents a considerable investment for
an animal with a reproductive span of two
months or less, especially in view of the fact
that both parents are foregoing additional
reproductive success while they remain
with their current brood. Larvae completed
development about seven days after hatching
and dispersed to pupate in the soil, emerging
as adults about 30 days later (Scott and
Traniello 1990b). Adults of the new generation
are found in late July and early August
in Nebraska. Wilson et al. (1984) suggested
that N. orbicollis appear to enter reproductive