A 2430 ha prescribed burn was conducted on Malheur National Wildlife Refuge, Harney County, Oregon in March 1985. About 35 days later, 11 greater sandhill crane (Grus canadensis tabida) pairs nested within the burned area; 9 of these hatched. The remaining 2 clutches were destroyed by coyotes (Canis latrans). Crane hatching success was significantly higher (P = 0.01) on the burned area (81.8%) than elsewhere (38.5%). Two factors were likely responsible for the higher success rate in the burn; nests were placed in deeper water and the smaI1 mammal prey base was temporarily reduced or eliminated resulting in reduced predator activity during incubation. Although hatching success was high for the burned area, no young fledged, probably because of increased predator pressure by late May

CORNELY, JOHN E.

EHLERS, BRADLEY D.

LITTLEFIELD, CARROLL D.

English

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University of Nebraska - Lincoln
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North American Crane Workshop Proceedings North American Crane Working Group
2001
EFFECTS OF AN EARLY SPRING BURN ON
GREATER SANDHILL CRANE NESTING
SUCCESS AT MALHEUR NATIONAL
WILDLIFE REFUGE, OREGON
CARROLL D. LITTLEFIELD
U.S. Fish and Wildlife Service, Malheur National Wildlife Refuge
JOHN E. CORNELY
U.S. Fish and Wildlife Service, Malheur National Wildlife Refuge
BRADLEY D. EHLERS
U.S. Fish and Wildlife Service, Malheur National Wildlife Refuge
Follow this and additional works at: http://digitalcommons.unl.edu/nacwgproc
Part of the Behavior and Ethology Commons, Biodiversity Commons, Ornithology Commons,
Population Biology Commons, and the Terrestrial and Aquatic Ecology Commons
This Article is brought to you for free and open access by the North American Crane Working Group at DigitalCommons@University of Nebraska -
Lincoln. It has been accepted for inclusion in North American Crane Workshop Proceedings by an authorized administrator of
DigitalCommons@University of Nebraska - Lincoln.
LITTLEFIELD, CARROLL D.; CORNELY, JOHN E.; and EHLERS, BRADLEY D., "EFFECTS OF AN EARLY SPRING BURN
ON GREATER SANDHILL CRANE NESTING SUCCESS AT MALHEUR NATIONAL WILDLIFE REFUGE, OREGON"
(2001). North American Crane Workshop Proceedings. 79.
http://digitalcommons.unl.edu/nacwgproc/79
EFFECTS OF AN EARLY SPRING BURN ON GREATER SANDHILL CRANE NESTING 
SUCCESS AT MALHEUR NATIONAL WILDLIFE REFUGE, OREGON 
CARROLL D. LITTLEFIELD/ U.S. Fish and Wildlife Service, Malheur National Wildlife Refuge, HC 72 Box 245, Princeton, 
OR 97721, USA 
JOHN E. CORNELY,2U.S. Fish and Wildlife Service, Malheur National Wildlife Refuge, HC 72 Box 245, Princeton, OR 97721, 
USA 
BRADLEY D. EHLERS,3 U.S. Fish and Wildlife Service, Malheur National Wildlife Refuge, HC 72 Box 245, Princeton, OR 
97721, USA 
Abstract: A 2430 ha prescribed burn was conducted on Malheur National Wildlife Refuge, Harney County, Oregon in March 
1985. About 35 days later, 11 greater sandhill crane (Grus canadensis tabida) pairs nested within the burned area; 9 of these 
hatched. The remaining 2 clutches were destroyed by coyotes (Canis latrans). Crane hatching success was significantly higher 
(P = 0.01) on the burned area (81.8%) than elsewhere (38.5%). Two factors were likely responsible for the higher success rate 
in the burn; nests were placed in deeper water and the smaI1 mammal prey base was temporarily reduced or eliminated resulting 
in reduced predator activity during incubation. Although hatching success was high for the burned area, no young fledged, 
probably because of increased predator pressure by late May. 
PROCEEDINGS NORTH AMERICAN CRANE WORKSHOP 8:45-47 
Key words: greater sandhill crane, Grus canadensis tabida, Malheur National Wildlife Refuge, nest success, Oregon, 
prescribed burn. 
An area of interspersed, seasonally flooded wetlands and 
shrub-covered uplands was burned on 30 March 1985 on 
Malheur National Wildlife Refuge (Malheur NWR), in 
southeastern Oregon. The burn area included about 2,430 ha 
of which 2,227 burned. Most of the unburned 200 ha area 
was black greasewood (Sarcobatus vermiculatus) flats with 
limited fine fuels. Previous prescribed burns at Malheur 
NWR were small «250 ha) and little information was 
collected on breeding greater sandhill crane responses to fire 
and subsequent nesting success. However, most pairs moved 
to adjoining unburned sites (Littlefield unpublished data). 
Although only 4 nests were monitored at previous burns, 
predators destroyed 3 and 1 was flooded. Predators remain-
ing on or near unburned sites consistently hunted the small 
burned plots. During the March 1985 fire, greater sandhill 
crane breeding territories located in marsh-meadow habitats 
were >95% burned. In this paper we report responses of 
nesting pairs and their nesting success in· an extensive area of 
habitat burned in the spring. 
IPresentaddress: HCR4 Box 212, Muleshoe, TX 79347, USA 
:!present address: U.S. Fish and Wildlife Service, Division of 
Migratory Birds, P.O. Box 25486, DFC, Denver, CO 80225, USA. 
3Present address: U.S. Fish and Wildlife Service, Sherburne 
National Wildlife Refuge, 17076 293rd Avenue, Zimmennan, MN 
55398, USA. 
45 
STUDY AREA AND METHODS 
The burned area's northern boundary was about 20 km 
south-southeast of Malheur NWR headquarters (51 km SSE 
of Burns, Harney County, Oregon, 43° 35'N, 118° 57'W) and 
extended south for 6.5 km. The width of the burn varied from 
2 km on the south to 4.8 km on the north. The West Canal 
and Donner und Blitzen River delineated the western and 
eastern burn boundaries, respectively. Within the area, 
meadows vegetated with various grass and sedge (Carex spp.) 
species dominated, whereas coarse emergents composed 
mostly of hardstem bulrush (Scirpus acutus), broad-fruited 
burreed (Sparganium eurycarpum), and common cattail 
(Typha latifolia) grew in depressions, ponds, sloughs, and 
channels. Interspersed among the wetland complex were 
extensive uplands vegetated with either big sagebrush 
(ArtemiSia tridentata). rabbitbrush (Chrysothamnus spp.), 
and/or greasewood. Irrigation by flooding began in April, 
and wetlands remained flooded through most of July. Grasses 
and sedges were burned within 1 to 8 cm of the soil substrate. 
A few scattered residual bulrush stands (usually <3 m diarn.) 
remained intact unburned in the area. 
The area was searched for crane nests on the ground 
during 6 May--6 June 1985. All nests were marked with laths 
at distances from 29--67 m. When a nest was found, incuba-
tion stage was determined by flotation (Westerskov 1950), 
and concealment category (Littlefield 1995a), vegetative type, 
water depth, and clutch size were recorded. Nests were 
revisited to assess clutch fates after expected hatching dates. 
46 EFFECTS OF A SPRIN"G BURN ON NESTING· Littlefield et al. Proc. North Am. Crane Workshop 8:2001 
The traditional method, or apparent estimator (ratio of 
number of clutches that hatched to number found) was used 
for determining nest success, as both terminated and active 
nests had an equally high probability of being located (John-
son and Shaffer 1990). We used a t-test to compare mean 
water depths at nest sites in the burned area with mean water 
depths at nests outside the burn. Differences in nesting 
success between burned and unburned sites were tested with 
2 x 2 contingency tables applying Yates correction for 
continuity (Sokal and Rohlf 1969). 
RESULTS 
Seventeen known crane nesting territories were in the 
area that burned. Of these, 11 (64.7%) pairs built nests 
within the burn area even though nesting cover was severely 
limited. Four nests were in the southwest, 6 in the west-
central, and 1 in the northwest portion of the burn. Six other 
pairs that had territories along the eastern edge shifted east 
and nested in adjacent unburned wetlands. Pairs with 
breeding territories in the western portion did not have this 
option, because the west boundary was bordered by the shrub-
covered slopes of the Jackass Mountains. Crane nest loca-
tions were mostly in or near small and isolated patches of 
unburned vegetation. 
Eight of 11 (72.7%) nests were in hardstem bulrush, 2 
(18.2%) in common cattail, and 1 (9.1%) in broad-fruited 
burreed. Most nests were in small stands of standing or 
burned emergents that provided limited concealment. 
Concealment was classified as poor for 9 (81.8%), fair for 1 
(9.1%), and good for 1 (9.1%). The only nest with good 
concealment was in a long, narrow channel with unburned 
bulrush. 
Crane nests within the burn were over deeper water than 
nests elsewhere on Malheur NWR in 1985 (t = 3.61, 46 df, P 
< 0.01). Water depths ranged from 10.4-62.5 cm (x = 42.4 
cm, SD = 15.0). Water depths for 39 nests in unburned 
locations ranged from moist soil to 64.5 cm (x = 23.6 cm, SD 
= 14.2). 
Nine of 11 (81.8%) clutches hatched; the other 2 were 
depredated by coyotes. All nests contained 2 eggs, and in the 
successful nests all eggs except 1, that was infertile, hatched; 
fertility rate was 94.4%. 
Most nesting was initiated during 1-7 May, shortly after 
breeding territories became flooded. One clutch each in 
cattail and bulrush was destroyed; both were poorly con-
cealed. Nest success was significantly greater ('1.2 = 6.46, 1 
df, P = 0.01) than success outside the burn. Success of 39 
nests assessed elsewhere on Malheur NWR in 1985 was 
38.5%; 1 clutch was abandoned and 23 were lost to predators. 
Coyotes destroyed 15 (38.5%), common ravens (Corvus 
corax) 7 (17.9%), and raccoon (Procyon lotor) 1 (2.6%). 
DISCUSSION 
Two factors may have been responsible for higher crane 
nest success within the burn: (1) nest placement was in deeper 
water, and (2) the small mammal prey base was temporarily 
reduced or eliminated. The cause for pairs nesting in deeper 
water was attributed to standing residual vegetation; many of 
the deeper marshes were moist at the time of the burn, 
resulting in a few small emergent patches surviving the fire. 
Coyotes in particular have a tendency to avoid crane nests in 
deep water on Malheur NWR (Littlefield 1995a). However, 
this would not account for the lack of predation by the other 
2 important egg consumers, common raven and raccoon. 
Therefore, we assume that a reduction of small mammal prey 
caused predators to temporarily leave. Small mammals, 
especially montane voles (Microtus monfanus), are an 
important food source for coyotes at Malheur NWR, particu-
larly before avian species start to nest (unpublished data). 
Coyotes had returned to the burn by late May and no 
young cranes were known to fledge. On 23 May 1985, a 
crane chick called from a dense new growth Baltic rush 
(Juncus balticus) stand in the burn area. Upon leaving the 
site, one of us (Littlefield) nearly collided with 2 coyotes as 
they rapidly approached the calling chick over a dike. 
Nearby, another coyote was close to a crane pair with 2 
chicks. The pair began to perform distraction displays 
(feigning), at which time the coyote initiated hunting behav-
ior. Littlefield's presence, however, resulted in the 3 coyotes 
quickly leaving. A survey on 27 May revealed no crane pairs 
or chicks, indicating all chicks had been lost, apparently to 
predation. 
VogI (1980 unpublished) suggested that little was known 
about the affects of fire on western alkaline marshes because 
of (1) the limited burning in the region and (2) the minimal 
effort by marsh managers to study, record, and publish results 
from their prescribed burns. However, studies on the effects 
of fire on small mammal populations was documented at 
Maiheur NWR by Comely et al. (1983), but generally there 
has been little documentation on the relationships of fire and 
other Great Basin wetland species. The purpose of this study 
was to report the impacts of a large prescribed wetland burn 
and its effects on crane reproductive success in a region 
known for high predation rates and excessive predator 
populations (Littlefield 1976, 1995a,b). We found that large 
prescribed burns may perhaps be a useful vegetation manage-
ment strategy, at least for wetlands inhabited by breeding 
greater sandhill cranes. Although we recorded higher nesting 
success, it did not contribute to successful fledging during the 
same year as the burn. Comparisons with success in succeed-
ing years was not feasible, as an intensive predator control 
program initiated in 1986 would have made comparisons 
biologically meaningless. 
Proc. North Am. Crane Workshop 8:2001 EFFECTS OF A SPRING BURN ON NESTING· Littlefield et al. 47 
ACKNOWLEDGMENTS 
We thank numerous U.S. Fish and Wildlife Service and 
Bureau of Land Management personnel who participated in 
completing the prescribed burn. Funding for this study was 
provided by the U.S. Fish and Wildlife Service. Special 
thanks are expressed to R. C. Drewien for his constructive 
editorial comments on an earlier draft of the manuscript. 
LITERATURE CITED 
Comely, J. E., C. M. Britton, and F. A. Sneva. 1983. Manipulation 
of flood meadow vegetation and observations on small mammal 
populations. Prairie Naturalist 15:16-22. 
Johnson, D. R., and T. L. Shaffer. 1990. Estimating nest success: 
when Mayfield wins. Auk 107:595-600. 
Littlefield, C. D. 1976. Productivity of greater sandhill cranes on 
MaIheurNational Wildlife Refuge, Oregon. Pages 86-92 in J. 
C. Lewis, editor. Proceedings of the international crane 
workshop. Oklahoma State University Publishing and Printing, 
Stillwater, Oklahoma, USA. 
Littlefield, C. D. 1995a. Sandhill crane nesting habitat, egg 
predators, and predator history on Malheur National Wildlife 
Refuge, Oregon. Northwestern Naturalist 76:137-143. 
Littlefield, C. D. 1995b. Demographics of a declining flock of 
greater sandhill cranes in Oregon. Wilson Bulletin 107:667-
674. 
Sokal, R. R., and F. J. Rohlf 1969. Biometry. W. H. Freeman, 
San Francisco, California, USA. 
Vogl, R. J. 1980 unpublished. A state-of-the-art review of the 
effects offire on wetland ecosystems. California State Univer-
sity, Los Angeles, California, USA. 
Westerskov, K. 1950. Methods for determining the age of game 
bird eggs. Journal of Wildlife Management 14:56-67. 


EFFECTS OF AN EARLY SPRING BURN ON GREATER SANDHILL CRANE NESTING
SUCCESS AT MALHEUR NATIONAL WILDLIFE REFUGE, OREGON

DigitalCommons@University of Nebraska

University of Nebraska - LincolnDigitalCommons@University of Nebraska - LincolnNorth American Crane Workshop Proceedings North American Crane Working Group2001EFFECTS OF AN EARLY SPRING BURN ONGREATER SANDHILL CRANE NESTINGSUCCESS AT MALHEUR NATIONALWILDLIFE REFUGE, OREGONCARROLL D. LITTLEFIELDU.S. Fish and Wildlife Service, Malheur National Wildlife RefugeJOHN E. CORNELYU.S. Fish and Wildlife Service, Malheur National Wildlife RefugeBRADLEY D. EHLERSU.S. Fish and Wildlife Service, Malheur National Wildlife RefugeFollow this and additional works at: http://digitalcommons.unl.edu/nacwgprocPart of the Behavior and Ethology Commons, Biodiversity Commons, Ornithology Commons,Population Biology Commons, and the Terrestrial and Aquatic Ecology CommonsThis Article is brought to you for free and open access by the North American Crane Working Group at DigitalCommons@University of Nebraska -Lincoln. It has been accepted for inclusion in North American Crane Workshop Proceedings by an authorized administrator ofDigitalCommons@University of Nebraska - Lincoln.LITTLEFIELD, CARROLL D.; CORNELY, JOHN E.; and EHLERS, BRADLEY D., "EFFECTS OF AN EARLY SPRING BURNON GREATER SANDHILL CRANE NESTING SUCCESS AT MALHEUR NATIONAL WILDLIFE REFUGE, OREGON"(2001). North American Crane Workshop Proceedings. 79.http://digitalcommons.unl.edu/nacwgproc/79EFFECTS OF AN EARLY SPRING BURN ON GREATER SANDHILL CRANE NESTING SUCCESS AT MALHEUR NATIONAL WILDLIFE REFUGE, OREGON CARROLL D. LITTLEFIELD/ U.S. Fish and Wildlife Service, Malheur National Wildlife Refuge, HC 72 Box 245, Princeton, OR 97721, USA JOHN E. CORNELY,2U.S. Fish and Wildlife Service, Malheur National Wildlife Refuge, HC 72 Box 245, Princeton, OR 97721, USA BRADLEY D. EHLERS,3 U.S. Fish and Wildlife Service, Malheur National Wildlife Refuge, HC 72 Box 245, Princeton, OR 97721, USA Abstract: A 2430 ha prescribed burn was conducted on Malheur National Wildlife Refuge, Harney County, Oregon in March 1985. About 35 days later, 11 greater sandhill crane (Grus canadensis tabida) pairs nested within the burned area; 9 of these hatched. The remaining 2 clutches were destroyed by coyotes (Canis latrans). Crane hatching success was significantly higher (P = 0.01) on the burned area (81.8%) than elsewhere (38.5%). Two factors were likely responsible for the higher success rate in the burn; nests were placed in deeper water and the smaI1 mammal prey base was temporarily reduced or eliminated resulting in reduced predator activity during incubation. Although hatching success was high for the burned area, no young fledged, probably because of increased predator pressure by late May. PROCEEDINGS NORTH AMERICAN CRANE WORKSHOP 8:45-47 Key words: greater sandhill crane, Grus canadensis tabida, Malheur National Wildlife Refuge, nest success, Oregon, prescribed burn. An area of interspersed, seasonally flooded wetlands and shrub-covered uplands was burned on 30 March 1985 on Malheur National Wildlife Refuge (Malheur NWR), in southeastern Oregon. The burn area included about 2,430 ha of which 2,227 burned. Most of the unburned 200 ha area was black greasewood (Sarcobatus vermiculatus) flats with limited fine fuels. Previous prescribed burns at Malheur NWR were small «250 ha) and little information was collected on breeding greater sandhill crane responses to fire and subsequent nesting success. However, most pairs moved to adjoining unburned sites (Littlefield unpublished data). Although only 4 nests were monitored at previous burns, predators destroyed 3 and 1 was flooded. Predators remain-ing on or near unburned sites consistently hunted the small burned plots. During the March 1985 fire, greater sandhill crane breeding territories located in marsh-meadow habitats were >95% burned. In this paper we report responses of nesting pairs and their nesting success in· an extensive area of habitat burned in the spring. IPresentaddress: HCR4 Box 212, Muleshoe, TX 79347, USA :!present address: U.S. Fish and Wildlife Service, Division of Migratory Birds, P.O. Box 25486, DFC, Denver, CO 80225, USA. 3Present address: U.S. Fish and Wildlife Service, Sherburne National Wildlife Refuge, 17076 293rd Avenue, Zimmennan, MN 55398, USA. 45 STUDY AREA AND METHODS The burned area's northern boundary was about 20 km south-southeast of Malheur NWR headquarters (51 km SSE of Burns, Harney County, Oregon, 43° 35'N, 118° 57'W) and extended south for 6.5 km. The width of the burn varied from 2 km on the south to 4.8 km on the north. The West Canal and Donner und Blitzen River delineated the western and eastern burn boundaries, respectively. Within the area, meadows vegetated with various grass and sedge (Carex spp.) species dominated, whereas coarse emergents composed mostly of hardstem bulrush (Scirpus acutus), broad-fruited burreed (Sparganium eurycarpum), and common cattail (Typha latifolia) grew in depressions, ponds, sloughs, and channels. Interspersed among the wetland complex were extensive uplands vegetated with either big sagebrush (ArtemiSia tridentata). rabbitbrush (Chrysothamnus spp.), and/or greasewood. Irrigation by flooding began in April, and wetlands remained flooded through most of July. Grasses and sedges were burned within 1 to 8 cm of the soil substrate. A few scattered residual bulrush stands (usually <3 m diarn.) remained intact unburned in the area. The area was searched for crane nests on the ground during 6 May--6 June 1985. All nests were marked with laths at distances from 29--67 m. When a nest was found, incuba-tion stage was determined by flotation (Westerskov 1950), and concealment category (Littlefield 1995a), vegetative type, water depth, and clutch size were recorded. Nests were revisited to assess clutch fates after expected hatching dates. 46 EFFECTS OF A SPRIN"G BURN ON NESTING· Littlefield et al. Proc. North Am. Crane Workshop 8:2001 The traditional method, or apparent estimator (ratio of number of clutches that hatched to number found) was used for determining nest success, as both terminated and active nests had an equally high probability of being located (John-son and Shaffer 1990). We used a t-test to compare mean water depths at nest sites in the burned area with mean water depths at nests outside the burn. Differences in nesting success between burned and unburned sites were tested with 2 x 2 contingency tables applying Yates correction for continuity (Sokal and Rohlf 1969). RESULTS Seventeen known crane nesting territories were in the area that burned. Of these, 11 (64.7%) pairs built nests within the burn area even though nesting cover was severely limited. Four nests were in the southwest, 6 in the west-central, and 1 in the northwest portion of the burn. Six other pairs that had territories along the eastern edge shifted east and nested in adjacent unburned wetlands. Pairs with breeding territories in the western portion did not have this option, because the west boundary was bordered by the shrub-covered slopes of the Jackass Mountains. Crane nest loca-tions were mostly in or near small and isolated patches of unburned vegetation. Eight of 11 (72.7%) nests were in hardstem bulrush, 2 (18.2%) in common cattail, and 1 (9.1%) in broad-fruited burreed. Most nests were in small stands of standing or burned emergents that provided limited concealment. Concealment was classified as poor for 9 (81.8%), fair for 1 (9.1%), and good for 1 (9.1%). The only nest with good concealment was in a long, narrow channel with unburned bulrush. Crane nests within the burn were over deeper water than nests elsewhere on Malheur NWR in 1985 (t = 3.61, 46 df, P < 0.01). Water depths ranged from 10.4-62.5 cm (x = 42.4 cm, SD = 15.0). Water depths for 39 nests in unburned locations ranged from moist soil to 64.5 cm (x = 23.6 cm, SD = 14.2). Nine of 11 (81.8%) clutches hatched; the other 2 were depredated by coyotes. All nests contained 2 eggs, and in the successful nests all eggs except 1, that was infertile, hatched; fertility rate was 94.4%. Most nesting was initiated during 1-7 May, shortly after breeding territories became flooded. One clutch each in cattail and bulrush was destroyed; both were poorly con-cealed. Nest success was significantly greater ('1.2 = 6.46, 1 df, P = 0.01) than success outside the burn. Success of 39 nests assessed elsewhere on Malheur NWR in 1985 was 38.5%; 1 clutch was abandoned and 23 were lost to predators. Coyotes destroyed 15 (38.5%), common ravens (Corvus corax) 7 (17.9%), and raccoon (Procyon lotor) 1 (2.6%). DISCUSSION Two factors may have been responsible for higher crane nest success within the burn: (1) nest placement was in deeper water, and (2) the small mammal prey base was temporarily reduced or eliminated. The cause for pairs nesting in deeper water was attributed to standing residual vegetation; many of the deeper marshes were moist at the time of the burn, resulting in a few small emergent patches surviving the fire. Coyotes in particular have a tendency to avoid crane nests in deep water on Malheur NWR (Littlefield 1995a). However, this would not account for the lack of predation by the other 2 important egg consumers, common raven and raccoon. Therefore, we assume that a reduction of small mammal prey caused predators to temporarily leave. Small mammals, especially montane voles (Microtus monfanus), are an important food source for coyotes at Malheur NWR, particu-larly before avian species start to nest (unpublished data). Coyotes had returned to the burn by late May and no young cranes were known to fledge. On 23 May 1985, a crane chick called from a dense new growth Baltic rush (Juncus balticus) stand in the burn area. Upon leaving the site, one of us (Littlefield) nearly collided with 2 coyotes as they rapidly approached the calling chick over a dike. Nearby, another coyote was close to a crane pair with 2 chicks. The pair began to perform distraction displays (feigning), at which time the coyote initiated hunting behav-ior. Littlefield's presence, however, resulted in the 3 coyotes quickly leaving. A survey on 27 May revealed no crane pairs or chicks, indicating all chicks had been lost, apparently to predation. VogI (1980 unpublished) suggested that little was known about the affects of fire on western alkaline marshes because of (1) the limited burning in the region and (2) the minimal effort by marsh managers to study, record, and publish results from their prescribed burns. However, studies on the effects of fire on small mammal populations was documented at Maiheur NWR by Comely et al. (1983), but generally there has been little documentation on the relationships of fire and other Great Basin wetland species. The purpose of this study was to report the impacts of a large prescribed wetland burn and its effects on crane reproductive success in a region known for high predation rates and excessive predator populations (Littlefield 1976, 1995a,b). We found that large prescribed burns may perhaps be a useful vegetation manage-ment strategy, at least for wetlands inhabited by breeding greater sandhill cranes. Although we recorded higher nesting success, it did not contribute to successful fledging during the same year as the burn. Comparisons with success in succeed-ing years was not feasible, as an intensive predator control program initiated in 1986 would have made comparisons biologically meaningless. Proc. North Am. Crane Workshop 8:2001 EFFECTS OF A SPRING BURN ON NESTING· Littlefield et al. 47 ACKNOWLEDGMENTS We thank numerous U.S. Fish and Wildlife Service and Bureau of Land Management personnel who participated in completing the prescribed burn. Funding for this study was provided by the U.S. Fish and Wildlife Service. Special thanks are expressed to R. C. Drewien for his constructive editorial comments on an earlier draft of the manuscript. LITERATURE CITED Comely, J. E., C. M. Britton, and F. A. Sneva. 1983. Manipulation of flood meadow vegetation and observations on small mammal populations. Prairie Naturalist 15:16-22. Johnson, D. R., and T. L. Shaffer. 1990. Estimating nest success: when Mayfield wins. Auk 107:595-600. Littlefield, C. D. 1976. Productivity of greater sandhill cranes on MaIheurNational Wildlife Refuge, Oregon. Pages 86-92 in J. C. Lewis, editor. Proceedings of the international crane workshop. Oklahoma State University Publishing and Printing, Stillwater, Oklahoma, USA. Littlefield, C. D. 1995a. Sandhill crane nesting habitat, egg predators, and predator history on Malheur National Wildlife Refuge, Oregon. Northwestern Naturalist 76:137-143. Littlefield, C. D. 1995b. Demographics of a declining flock of greater sandhill cranes in Oregon. Wilson Bulletin 107:667-674. Sokal, R. R., and F. J. Rohlf 1969. Biometry. W. H. Freeman, San Francisco, California, USA. Vogl, R. J. 1980 unpublished. A state-of-the-art review of the effects offire on wetland ecosystems. California State Univer-sity, Los Angeles, California, USA. Westerskov, K. 1950. Methods for determining the age of game bird eggs. Journal of Wildlife Management 14:56-67. 

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EFFECTS OF AN EARLY SPRING BURN ON GREATER SANDHILL CRANE NESTING SUCCESS AT MALHEUR NATIONAL WILDLIFE REFUGE, OREGON

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