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The fifteen Pinon Jay vocalizations were examined with the aid of a sonograph. Statements are made about their physical characteristics, functions, and in some cases, their relationship with other calls and displays. One vocali­zation, the Near, was analyzed for components that would allow recognition of individual Pinon Jays. Many vocalizations are extremely graded in their renditions. Three displays not previously mentioned in the literature are also described.

Agonistic behaviour of Gila Woodpeckers (Centurus uropygialis), including vocalizations, visual displays and other related behaviours, is described. Aggressive interactions with both con- and hetero-specifics were analyzed by stochastic processes. Results indicate that Gila Woodpeckers are far less aggressive than qualitative descriptions suggest and reasons for this discrepancy are presented. The ecological correlates of Gila Woodpecker aggression were investigated and it appears that most aggression is related to defense of areas both intraspecifically and interspecifically. The effects of the two types of territoriality on the distribution of the species involved were compared and found to be significantly different. A model is presented to explain how an individual can defend more than one territory which overlap in time and space.

An immune response to spermatozoa may result in the production of autoantibodies to sperm. Most studies of antisperm antibody have depended on sperm agglutination or sperm immobilization which only detect antibodies reacting with cell surface antigen. In the study reported here indirect immunofluorescence was used to examine antisperm antibodies to all components of sperm in vasectomized males. These antibodies were used to study the nature of sperm­specific antigens, located in subcellular regions of the human spermatozoa. The incidence of antisperm antibodies in vasectomized patients rises from 61% before surgery to 90% nine months after surgery. The antibodies present before surgery were designated "natural" antibodies to sperm. These antibodies increased in titer and incidence after surgery. Three antibodies were considered "immune" antibodies, as they developed after vasectomy. These were speckled anti-acrosome, antisperm nucleus and anti-tail antibodies. The immunoglobulin classes of the natural antibodies were IgG and IgM, while the immune antibodies were predominantly IgG. The sperm antigens were divided into two groups according to their accessibility to reaction with antibody. The first group was detected on smears of methanol fixed sperm and were classified as accessible antigens. These reacted with anti-acrosomal (diffuse and speckled), anti­equatorial, anti-postacrosomal, and anti-tail antibodies. The second group was inaccessible unless the sperm were treated with the reducing agent dithiothreitol and trypsin before smears were made. The accessible antigens were removed by this treatment. These two addition 1 antigens detected in treated sperm were found in the perm nucleus and in the midpiece of the tail. Cross-reaction of antisperm antibodies with other tissues, determined that they were directed to perm-specific antigens. Cross-reaction of antisperm nucleus antibody with basic nuclear proteins gave positive evidence for the identification of the

The invasion of a high elevation burn (3500 m) by Engelmann spruce (Picea engelmannii Parry) was investigated on the Santa Fe National Forest in north-central New Mexico. Population analyses and a field germination test of spruce seeds under various treatments were performed. The resistance of soil moisture blocks and soil temperatures were measured. The fire which occurred in 1886 eliminated a climax spruce-fir forest and resulted in a subalpine grassland at elevations above the zone where aspen (Populus tremuloides Michx.) has invaded. The estimated crown coverage of trees in the grassland is less than 5%. Engelmann spruce comprises 92.5% of the trees in sampling plots, while limber pine (Pinus flexilis James) and corkbark fir (Abies lasiocarpa var. arizonica (Merriam) Lemm.) comprise 4.1% and 3.4%, respectively. The density of trees in all size classes is 7.3 trees/100 m2. The size class distribution of spruce shows a marked J-shape which is assumed to be an indication of an increasing rate of establishment. More rapid invasion seems to occur on north aspects. Establishment was found to be a non-random process, following a clumped distribution; however, no site factor was found to be correlated with tree density. The diameter growth rate of Engelmann spruce was determined to be 0.77 cm/year. The growth rate for spruce greater than 10 cm in diameter was found to be neither increasing or decreasing with age. The deviations in an age distribution of spruce were positively correlated with June plus July precipitation during this years of establishment. The treatments had significant effects on the germination and seedling survival of Engelmann spruce. Black plastic mulch increased germination; however, it also increased seedling mortality. Pine bark mulch treatment and greenhouse (polyethylene enclosure) treatment decreased germination, while the disturbed treatment did not appear to affect germination or mortality. The amount and distribu

A new transport and holding medium, designated medium #505, has been formulated and tested against standard, commercially available media. The medium is a chemically defined mixture. The ingredients include: sodium chloride, sodium thioglycollate, buffered agar, Amberlite CG-400, methylene blue and IsoVitalex. The experimental design included two phases. During Phase I, transport media were formulated and tested for their ability to maintain a viable culture of the non-pathogen Neisseria perflava for at least 21 days at ambient temperature (25° C). In Phase II, media that were able to maintain Neisseria perflava for at least 21 days were tested for their ability to maintain a viable culture of the pathogen Neisseria gonorrhoeae for 7 days.

This study measures the magnitude of the competition between two nocturnal, desert rodents, Dipodomys ordii and D. merriami, on 10 unenclosed, 16 hectare plots along a narrow band of sympatry in south-central New Mexico. Population perturbations of one or the other species were periodically performed on eight of the plots, while natural population changes were monitored on two controls. The relative numerical responses of the kangaroo rats to these perturbations are thought to reflect the true magnitude of their competitive interaction.

A bacterial survey of fecal coliforms, fecal streptococci, Arizona and Salmonella was made of the waters of the Rio Grande, its adjoining canals and ditches, and of the well water of three pueblos along the Rio Grande in New Mexico. The river and ditch survey consisted of sampling 11 sites from Cochiti Bridge south to the Bernalillo Acequia at Bernalillo, and took place between September, 1971 and November, 1972. Water was collected from six sites in Cochiti Village, five sites in Santo Domingo Village, and seven sites from San Felipe Village between May 25, 1972 and November 14, 1972. Six Salmonella enteritidis isolations were made including serotypes carrau, newport, belem, muenchen, and bredeney from four sites - Cochiti Bridge, Sili Main Canal, Bernalillo Acequia, and San Felipe Bridge. Two Arizona isolations were made from Cochiti East Side Main Canal and Bernalillo Acequia. All of the isolates were found in July and August when surface water temperatures ranged from 22.8 to 24.0 ° C. Fecal coliforms and fecal streptococci were counted using Millipore Filter techniques and the fecal coliform/ fecal streptococcus ratios (FC/FS) were computed. There appeared to be a seasonal pattern; the quantity of both organisms reached their greatest numbers during the warmer months of May to September. However, the FC/FS ratios had no apparent pattern and showed no correlation other than that Salmonella was not isolated when the ratio was less than 9.7. Samples collected from the pueblos showed contamination at various sites. An attempt was made to find causes of contamination and measures were taken in each pueblo to try and eliminate it.

Three species of Triatorna were studied in this investigation: T. rubida uhleri (Neiva), _T. protracta protracta (Uhler), and T. recurva (Stal) (Hemiptera:Reduviidae). These blood-sucking bugs are ectoparasites of vertebrate animals. Triatoma rubida uhleri (Neiva) is the most common conenose bug in southern Arizona. At certain seasons of the year Triatoma bugs enter homes and bite people causing an allergic reaction in sensitized individuals. The purpose of this study was to determine cause of flight, time of day and r season of the year most individuals fly, effects of various physical factors on flights and distances flown. This research was conducted at lights in Sabino Canyon, northeast of Tucson, Arizona. A black light was operated 4 to 6 nights per week during the summers of 1972 and 1973. For each Triatoma bug collected physical conditions (temperature, relative humidity, cloud cover, moonlight, wind speed and direction) and time of arrival were noted. Computer analysis of the data was performed using programs written in FORTRAN IV and a prepared program (BMD 02R) from UCLA Health Sciences Computing Facility. Lodges of Neotoma albigula Hartley, the natural host of Triatoma rubida and TT. protracta protracta, were examined for the presence of bugs during all seasons of the year. Seventy-nine lodges were examined. A total of 1107 Triatominae were collected at lights and traps and 941 from Neotoma lodges. Twelve species of reduviids other than Triatominae were also collected at the black lights. Three species of buprestids were collected on sticky traps. Desert tortoises. banded geckos and scorpions were found in Neotoma lodges. Triatoma rubida uhleri bugs overwinter as 5th instar nymphs. As soon as average temperatures warm up to 23° to 25°C, the 5th instar nymphs begin molting to adults. This produces large numbers of adult bugs in early summer. T. rubida has a short adult life span; by fall very few adult bugs are left alive. Triatoma flights appear to be due

The invasion of a high elevation burn (3500 m) by Engelmann spruce (Picea engelmannii Parry) was investigated on the Santa Fe National Forest in north-central New Mexico. Population analyses and a field germination test of spruce seeds under various treatments were performed. The resistance of soil moisture blocks and soil temperatures were measured. The fire which occurred in 1886 eliminated a climax spruce-fir forest and resulted in a subalpine grassland at elevations above the zone where aspen (Populus tremuloides Michx.) has invaded. The estimated crown coverage of trees in the grassland is less than 5%. Engelmann spruce comprises 92.5% of the trees in sampling plots, while limber pine (Pinus flexilis James) and corkbark fir (Abies lasiocarpa var. arizonica (Merriam) Lemm.) comprise 4.1% and 3.4%, respectively. The density of trees in all size classes is 7.3 trees/100 m2. The size class distribution of spruce shows a marked J-shape which is assumed to be an indication of an increasing rate of establishment. More rapid invasion seems to occur on north aspects. Establishment was found to be a non-random process, following a clumped distribution; however, no site factor was found to be correlated with tree density. The diameter growth rate of Engelmann spruce was determined to be 0.77 cm/year. The growth rate for spruce greater than 10 cm in diameter was found to be neither increasing or decreasing with age. The deviations in an age distribution of spruce were positively correlated with June plus July precipitation during this years of establishment. The treatments had significant effects on the germination and seedling survival of Engelmann spruce. Black plastic mulch increased germination; however, it also increased seedling mortality. Pine bark mulch treatment and greenhouse (polyethylene enclosure) treatment decreased germination, while the disturbed treatment did not appear to affect germination or mortality. The amount and distribu

The fifteen Pinon Jay vocalizations were examined with the aid of a sonograph. Statements are made about their physical characteristics, functions, and in some cases, their relationship with other calls and displays. One vocali­zation, the Near, was analyzed for components that would allow recognition of individual Pinon Jays. Many vocalizations are extremely graded in their renditions. Three displays not previously mentioned in the literature are also described.

Agonistic behaviour of Gila Woodpeckers (Centurus uropygialis), including vocalizations, visual displays and other related behaviours, is described. Aggressive interactions with both con- and hetero-specifics were analyzed by stochastic processes. Results indicate that Gila Woodpeckers are far less aggressive than qualitative descriptions suggest and reasons for this discrepancy are presented. The ecological correlates of Gila Woodpecker aggression were investigated and it appears that most aggression is related to defense of areas both intraspecifically and interspecifically. The effects of the two types of territoriality on the distribution of the species involved were compared and found to be significantly different. A model is presented to explain how an individual can defend more than one territory which overlap in time and space.

The objectives of this study were threefold: 1) to determine whether buntings prefer cultivated areas or native grassland for nest sites; 2) to determine whether nests destroyed by agricultural practices result in renesting in "safer" habitats (such as grassland); and 3) to elucidate the life history of this species near the periphery of its breeding range. Preferred nesting habitat was milo stubble (grain sorghum), with 54 of 83 nests (65.1%), followed by native prairie (20.5%), alfalfa (8.4%), and planted grass (6.0%). Clutch size (70 nests) averaged 4.8 eggs per nest. Females did most (84.3%) of the incubation. Overall nesting success was low (20.5%), and was highest in alfalfa, followed by native prairie, milo stubble, and planted grass. Preparation of fields for planting, predation, and human disturbance were major reasons for nest failures. Productivity was highest in alfalfa, followed by milo stubble, native prairie, and planted grass. Cowbird parasitism occurred in 20.8 per cent of the nests used for analysis. Only one nest was successful and no cowbirds fledged. Parasitism rates were slightly greater in stubble than in grassland. Local abundance fell below the 7-year recorded average. Attempts to correlate abundance with precipitation totals proved inconclusive. No evidence of renesting was found.

The purpose of this study was to inventory the ecological status of Lake Atwood, near Atwood, Kansas, and to formulate a feasible renovation plan to restore the lake to a more balanced ecological state. Results of the study indicate that it is economically feasible to renovate Lake Atwood and to create a Waterfowl Refuge, a Prairie Park and a Nature Trail Area adjacent to the Lake. The total estimated cost for the project is $681,000.

Brown-headed Cowbirds were studied in Ellis County, Kansas from February, 1973 to August, 1974. Objectives of the study were to 1) determine the frequency and effect of cowbird parasitism in a prairie habitat 2) determine adaptations of host species to parasitism and, 3) determine population structure and movements of cowbirds banded in Ellis County. One hundred and eleven of 520 nests of host species (21%) were parasitized. The frequency of parasitism varied from a low of 2.7 per cent (Say's Phoebe) to a high of 100 per cent (Cardinal). All but one grassland host species received moderate to heavy parasitism. Parasitized nests fledged one less host (.5 per nest) than non-parasitized nests (1.5 per nest). Only .3 cowbirds fledged per nest. Probable adaptations to parasitism were nesting prior to the cowbirds breeding season by Horned Larks, aggression by colonies of Red-winged Blackbirds, and nest desertion and removal of cowbird eggs by Lark Buntings. A total of 9,651 cowbirds were banded during this study. Adults departed from Ellis County by mid-August, whereas transient populations of immatures were present until November. Observations of color-marked individuals were reported near Buffalo, Oklahoma, Dodge City, Rush Center, and McCracken, Kansas.

The King, Sora, and Virginia Rails were studied at the Cheyenne Bottoms Waterfowl Management Area in Barton County, Kansas in 1974. An auditory index of these three rail populations was attempted with the use of tape-recorded calls. It is believed that the auditory index technique can be applied to breeding Virginia Rail populations. Because of a paucity of responses, no conclusions could be made as to the suitability of such a technique for use on King Rail and Sora populations. To further investigate rail movements, rails were trapped from 6 June to 10 October. A total of 39 King Rails, three Soras, and 225 Virginia Rails was trapped and banded. Conservative population estimates of the King and Virginia Rail populations were made. Adult King Rails were estimated to number between 20 and 40 pairs and adult Virginia Rails between 200 and 400 pairs. Nesting observations were made on a total of three King Rail nests, one Virginia Rail nest, and one Sora nest. Percentage composition of plant species was determined for each study area. A notation of plant species and depth of water was made for each individual rail observation (both visual and auditory) in an effort to determine habitat preferences.

Body composition, energy content, basic weight, and lipid cycles were determined for populations of the plains pocket gopher (Geomys bursarius) and the yellow-faced pocket gopher (Pappogeomys castanops) in Kansas. Lipid content calculated as a percentage of dry body weight varied from 11.35 to 32.20 per cent in G. bursarius and from 14.61 to 30.04 in P. castanops. Seasonal means for energy content ranged from 1.29 to 1.57 kcal/g live weight for G. bursarius and from 1.38 to 1.62 for P. castanops. Per cent ash and water varied from 17.55 to 18.64 and from 67.13 to 72.59, respectively. In both males and females of G. bursarius, basic weight increased from autumn until winter, whereas in males of P. castanops basic weight decreased from summer until winter but in females basic weight decreased only from autumn until winter. Values for per cent lipids dry body weight, per cent lipids live body weight, and kilocalories per gram biomass were significantly lower for subadult P. castanops than adult P. castanops during the summer but per cent water was significantly higher. Seasonal lipid cycles were similar in the two species, with the low in early or middle summer and the high in late winter or early spring. It is postulated that lipid cycles of pocket gophers are the result of energetically expensive activities associated with breeding and burrowing. Numerous ecological studies (Downhower and Hall, 1966; Ingles, 1952; Miller, 1964; Wilks, 1963) have been conducted on pocket gophers of the genera Geomys and Thomomys; however, little has been published on Pappogeomys, and no investigation of any of these genera has dealt with lipid cycles. Fleharty et al. (1973) summarized data on body composition, lipid cycles, and lipid deposition of four species of rodents in Kansas and attributed differences in lipid cycles among those rodents to historic and evolutionary factors. The purposes of this study were to elucidate lipid cycles and body composition for the two species of pock

Ecological parameters for white-footed mice (Peromyscus leucopus) were estimated from data collected by live-trapping in a riparian habitat in west-central Kansas from October of 1972 through September of 1973. The distribution of white-footed mice on the study area was irregular, and revealed a definite preference for a wooded habitat dominated by American elm (Ulmus americana), box elder (Acer negundo), green ash (Fraxinus pennsylvanica), and honey locust (Gleditsia triacanthos) . Lowest crude densities (7.2/ha) were recorded for late spring and early summer and the highest (40.5/ha) during autumn (October). Ecological densities fluctuated from a summer low of 0/ha in less preferred habitats to autumn (October, 1972) and summer (July, 1973) highs of 124/ha and 111/ha, respectively, in the preferred habitat. Home ranges of males (0.07 +/- 0.03 ha) and females (0.03 +/- 0.01 ha) did not differ significantly. Greatest distances traveled by males did not differ significantly from those of females although a few males traversed more than 100 m in 24 hours during the summer. Population turnover was 35% complete after the first month and 99% complete after only six months. During the study, 37 males and 37 females were on the study area an average of 74 and 82 days, respectively. Biannual peaks in population density occurred after the breeding periods in early autumn (September) and summer (June). The September and June cohorts each produced 31% of the total newborn young. Rates of individual and biomass turnover were 5.94 and 2.01 times per year, respectively. Secondary productivity varied from a low of 0.004g/ha/day in December to a high of 7.1/g/ha/day in June. The white-footed mouse (Peromyscus leucopus) has an extensive geographic distribution in the western hemisphere (Hall and Kelson, 1959). Kansas is at the western periphery of the range of the species; P. leucopus occurs throughout the state except in four western counties (Fleharty and Stadel, 1968). Absence of

Herbage dynamics of three plant communities were estimated from June, 1971, to May, 1972, on a Mixed Prairie grassland in Trego County, Kansas. Specific functional attributes estimated were: (1) net primary production, (2) productivity rates, and (3) standing crops of mulch. The relationships of available soil moisture to net primary production was assessed. The three communities sampled were Andropogon gerardi, Bouteloua gracilis-Buchloe dactyloides, and Bouteloua curtipendula-Bouteloua gracilis. Net primary production for these three communities was estimated at 430, 238, and 257 g/m2, respectively. Forbs contributed 45% of the estimate of net primary production (257 g/m2) in the Bouteloua curtipendula-Bouteloua gracilis community. In the Andropogon gerardi community, daily productivity rates for Andropogon gerardi were relatively stable from June to August, 1971, whereas rates for total green herbage increased during the same period. Rate of production for Bouteloua gracilis plus Buchloe dactyloides in the Bouteloua gracilis-Buchloe dactyloides community was highest in August, 1971. Bromus japonicas was the only major cool season species of grass in this community and reached its peak standing crop and highest productivity rate in May, 1972. Mulch was the dominant biomass component in all three communities and levels remained relatively constant during the sample period.

Four thirteen-lined ground squirrels (Spermophilus tridecemlineatus) were trained on a DRL 20-sec schedule and given the opportunity to emit a mediating behavior (i.e., running in an activity wheel or manipulating a cork ball attached to a switch). All of the subjects used the manipulanda provided, allowing quantification of the mediating behavior. Results indicated that the number of mediating responses were correlated with the length of interresponse time (IRT) for all animals, and that similarities in the two mediating response data were present. These results are consistent with the theory that mediating behavior facilitates performance on a differential reinforcement of low response rates (DRL) schedule.

Analyses of morphological and mensural variation in the molar dentitions of several populations of Microtus pennsylvanicus inhabiting mainland, peninsular, archipelagic, and insular environments in southern New England enabled elucidation of recent evolutionary trends in those populations. Dental evolution in voles of the pennsylvanicus lineage of the genus Microtus generally proceeds toward increased occlusal complexity in mainland habitats but toward decreased occlusal complexity on islands. Intraspecific and interspecific interactions play important roles in determining dental complexity. Quantitatively, insular populations usually are more variable than mainland populations because of the more intense selective forces that exist in insular environments. Likewise, intense K-selection on islands, as compared with that on the mainland, is responsible for the fact that microtine rodents generally are larger on islands than on the adjacent mainland. Factors responsible for increased natural selection on islands are discussed, and analysis of intrapopulational variation is shown to be useful as a measure of the rate of evolution.

The nesting ecology of the Eastern Phoebe and Say's (Sayornis phoebe and S. saya, respectively) was compared during the 1973 and 1974 breeding seasons to determine the factor (s) that might limit their distribution in a sympatric area in west-central Kansas. The study area, Ellis County, includes the extreme breeding range for both species. Overall density of Eastern Phoebes is low (one pair per 26,000 acres) because of a paucity of riparian woodland. Results of field observation and censusing suggest that the density of Say's Phoebes is comparable to that of Eastern Phoebes. Eastern Phoebes were restricted to bridges in riparian areas; Say's Phoebes selected a variety of structures as nest sites throughout open rangeland and farm land in this area. Only one pair of phoebes occupied a given nest site; therefore, they are obviously territorial. Because foraging areas did not overlap, inter-specific hostility resulted in competition for nest sites (bridges) in intermediate habitat. However, densities were low and territorial or competitive interactions were rare events. This study suggests that for the Eastern Phoebe, the only obvious factor limiting the breeding range to the west was a decrease in suitable habitat; competition, as a limiting factor, seems to be of little importance. It appears that the same is true to the east for the Say’s Phoebe.

The purpose of this study was to inventory the ecological status of Lake Atwood, near Atwood, Kansas, and to formulate a feasible renovation plan to restore the lake to a more balanced ecological state. Results of the study indicate that it is economically feasible to renovate Lake Atwood and to create a Waterfowl Refuge, a Prairie Park and a Nature Trail Area adjacent to the Lake. The total estimated cost for the project is $681,000.

The King, Sora, and Virginia Rails were studied at the Cheyenne Bottoms Waterfowl Management Area in Barton County, Kansas in 1974. An auditory index of these three rail populations was attempted with the use of tape-recorded calls. It is believed that the auditory index technique can be applied to breeding Virginia Rail populations. Because of a paucity of responses, no conclusions could be made as to the suitability of such a technique for use on King Rail and Sora populations. To further investigate rail movements, rails were trapped from 6 June to 10 October. A total of 39 King Rails, three Soras, and 225 Virginia Rails was trapped and banded. Conservative population estimates of the King and Virginia Rail populations were made. Adult King Rails were estimated to number between 20 and 40 pairs and adult Virginia Rails between 200 and 400 pairs. Nesting observations were made on a total of three King Rail nests, one Virginia Rail nest, and one Sora nest. Percentage composition of plant species was determined for each study area. A notation of plant species and depth of water was made for each individual rail observation (both visual and auditory) in an effort to determine habitat preferences.

Body composition, energy content, basic weight, and lipid cycles were determined for populations of the plains pocket gopher (Geomys bursarius) and the yellow-faced pocket gopher (Pappogeomys castanops) in Kansas. Lipid content calculated as a percentage of dry body weight varied from 11.35 to 32.20 per cent in G. bursarius and from 14.61 to 30.04 in P. castanops. Seasonal means for energy content ranged from 1.29 to 1.57 kcal/g live weight for G. bursarius and from 1.38 to 1.62 for P. castanops. Per cent ash and water varied from 17.55 to 18.64 and from 67.13 to 72.59, respectively. In both males and females of G. bursarius, basic weight increased from autumn until winter, whereas in males of P. castanops basic weight decreased from summer until winter but in females basic weight decreased only from autumn until winter. Values for per cent lipids dry body weight, per cent lipids live body weight, and kilocalories per gram biomass were significantly lower for subadult P. castanops than adult P. castanops during the summer but per cent water was significantly higher. Seasonal lipid cycles were similar in the two species, with the low in early or middle summer and the high in late winter or early spring. It is postulated that lipid cycles of pocket gophers are the result of energetically expensive activities associated with breeding and burrowing. Numerous ecological studies (Downhower and Hall, 1966; Ingles, 1952; Miller, 1964; Wilks, 1963) have been conducted on pocket gophers of the genera Geomys and Thomomys; however, little has been published on Pappogeomys, and no investigation of any of these genera has dealt with lipid cycles. Fleharty et al. (1973) summarized data on body composition, lipid cycles, and lipid deposition of four species of rodents in Kansas and attributed differences in lipid cycles among those rodents to historic and evolutionary factors. The purposes of this study were to elucidate lipid cycles and body composition for the two species of pock

Herbage dynamics of three plant communities were estimated from June, 1971, to May, 1972, on a Mixed Prairie grassland in Trego County, Kansas. Specific functional attributes estimated were: (1) net primary production, (2) productivity rates, and (3) standing crops of mulch. The relationships of available soil moisture to net primary production was assessed. The three communities sampled were Andropogon gerardi, Bouteloua gracilis-Buchloe dactyloides, and Bouteloua curtipendula-Bouteloua gracilis. Net primary production for these three communities was estimated at 430, 238, and 257 g/m2, respectively. Forbs contributed 45% of the estimate of net primary production (257 g/m2) in the Bouteloua curtipendula-Bouteloua gracilis community. In the Andropogon gerardi community, daily productivity rates for Andropogon gerardi were relatively stable from June to August, 1971, whereas rates for total green herbage increased during the same period. Rate of production for Bouteloua gracilis plus Buchloe dactyloides in the Bouteloua gracilis-Buchloe dactyloides community was highest in August, 1971. Bromus japonicas was the only major cool season species of grass in this community and reached its peak standing crop and highest productivity rate in May, 1972. Mulch was the dominant biomass component in all three communities and levels remained relatively constant during the sample period.

Brown-headed Cowbirds were studied in Ellis County, Kansas from February, 1973 to August, 1974. Objectives of the study were to 1) determine the frequency and effect of cowbird parasitism in a prairie habitat 2) determine adaptations of host species to parasitism and, 3) determine population structure and movements of cowbirds banded in Ellis County. One hundred and eleven of 520 nests of host species (21%) were parasitized. The frequency of parasitism varied from a low of 2.7 per cent (Say's Phoebe) to a high of 100 per cent (Cardinal). All but one grassland host species received moderate to heavy parasitism. Parasitized nests fledged one less host (.5 per nest) than non-parasitized nests (1.5 per nest). Only .3 cowbirds fledged per nest. Probable adaptations to parasitism were nesting prior to the cowbirds breeding season by Horned Larks, aggression by colonies of Red-winged Blackbirds, and nest desertion and removal of cowbird eggs by Lark Buntings. A total of 9,651 cowbirds were banded during this study. Adults departed from Ellis County by mid-August, whereas transient populations of immatures were present until November. Observations of color-marked individuals were reported near Buffalo, Oklahoma, Dodge City, Rush Center, and McCracken, Kansas.

The objectives of this study were threefold: 1) to determine whether buntings prefer cultivated areas or native grassland for nest sites; 2) to determine whether nests destroyed by agricultural practices result in renesting in "safer" habitats (such as grassland); and 3) to elucidate the life history of this species near the periphery of its breeding range. Preferred nesting habitat was milo stubble (grain sorghum), with 54 of 83 nests (65.1%), followed by native prairie (20.5%), alfalfa (8.4%), and planted grass (6.0%). Clutch size (70 nests) averaged 4.8 eggs per nest. Females did most (84.3%) of the incubation. Overall nesting success was low (20.5%), and was highest in alfalfa, followed by native prairie, milo stubble, and planted grass. Preparation of fields for planting, predation, and human disturbance were major reasons for nest failures. Productivity was highest in alfalfa, followed by milo stubble, native prairie, and planted grass. Cowbird parasitism occurred in 20.8 per cent of the nests used for analysis. Only one nest was successful and no cowbirds fledged. Parasitism rates were slightly greater in stubble than in grassland. Local abundance fell below the 7-year recorded average. Attempts to correlate abundance with precipitation totals proved inconclusive. No evidence of renesting was found.

Analyses of morphological and mensural variation in the molar dentitions of several populations of Microtus pennsylvanicus inhabiting mainland, peninsular, archipelagic, and insular environments in southern New England enabled elucidation of recent evolutionary trends in those populations. Dental evolution in voles of the pennsylvanicus lineage of the genus Microtus generally proceeds toward increased occlusal complexity in mainland habitats but toward decreased occlusal complexity on islands. Intraspecific and interspecific interactions play important roles in determining dental complexity. Quantitatively, insular populations usually are more variable than mainland populations because of the more intense selective forces that exist in insular environments. Likewise, intense K-selection on islands, as compared with that on the mainland, is responsible for the fact that microtine rodents generally are larger on islands than on the adjacent mainland. Factors responsible for increased natural selection on islands are discussed, and analysis of intrapopulational variation is shown to be useful as a measure of the rate of evolution.

Ecological parameters for white-footed mice (Peromyscus leucopus) were estimated from data collected by live-trapping in a riparian habitat in west-central Kansas from October of 1972 through September of 1973. The distribution of white-footed mice on the study area was irregular, and revealed a definite preference for a wooded habitat dominated by American elm (Ulmus americana), box elder (Acer negundo), green ash (Fraxinus pennsylvanica), and honey locust (Gleditsia triacanthos) . Lowest crude densities (7.2/ha) were recorded for late spring and early summer and the highest (40.5/ha) during autumn (October). Ecological densities fluctuated from a summer low of 0/ha in less preferred habitats to autumn (October, 1972) and summer (July, 1973) highs of 124/ha and 111/ha, respectively, in the preferred habitat. Home ranges of males (0.07 +/- 0.03 ha) and females (0.03 +/- 0.01 ha) did not differ significantly. Greatest distances traveled by males did not differ significantly from those of females although a few males traversed more than 100 m in 24 hours during the summer. Population turnover was 35% complete after the first month and 99% complete after only six months. During the study, 37 males and 37 females were on the study area an average of 74 and 82 days, respectively. Biannual peaks in population density occurred after the breeding periods in early autumn (September) and summer (June). The September and June cohorts each produced 31% of the total newborn young. Rates of individual and biomass turnover were 5.94 and 2.01 times per year, respectively. Secondary productivity varied from a low of 0.004g/ha/day in December to a high of 7.1/g/ha/day in June. The white-footed mouse (Peromyscus leucopus) has an extensive geographic distribution in the western hemisphere (Hall and Kelson, 1959). Kansas is at the western periphery of the range of the species; P. leucopus occurs throughout the state except in four western counties (Fleharty and Stadel, 1968). Absence of

Four thirteen-lined ground squirrels (Spermophilus tridecemlineatus) were trained on a DRL 20-sec schedule and given the opportunity to emit a mediating behavior (i.e., running in an activity wheel or manipulating a cork ball attached to a switch). All of the subjects used the manipulanda provided, allowing quantification of the mediating behavior. Results indicated that the number of mediating responses were correlated with the length of interresponse time (IRT) for all animals, and that similarities in the two mediating response data were present. These results are consistent with the theory that mediating behavior facilitates performance on a differential reinforcement of low response rates (DRL) schedule.

Body composition, energy content, basic weight, and lipid cycles were determined for populations of the plains pocket gopher (Geomys bursarius) and the yellow-faced pocket gopher (Pappogeomys castanops) in Kansas. Lipid content calculated as a percentage of dry body weight varied from 11.35 to 32.20 per cent in G. bursarius and from 14.61 to 30.04 in P. castanops. Seasonal means for energy content ranged from 1.29 to 1.57 kcal/g live weight for G. bursarius and from 1.38 to 1.62 for P. castanops. Per cent ash and water varied from 17.55 to 18.64 and from 67.13 to 72.59, respectively. In both males and females of G. bursarius, basic weight increased from autumn until winter, whereas in males of P. castanops basic weight decreased from summer until winter but in females basic weight decreased only from autumn until winter. Values for per cent lipids dry body weight, per cent lipids live body weight, and kilocalories per gram biomass were significantly lower for subadult P. castanops than adult P. castanops during the summer but per cent water was significantly higher. Seasonal lipid cycles were similar in the two species, with the low in early or middle summer and the high in late winter or early spring. It is postulated that lipid cycles of pocket gophers are the result of energetically expensive activities associated with breeding and burrowing. Numerous ecological studies (Downhower and Hall, 1966; Ingles, 1952; Miller, 1964; Wilks, 1963) have been conducted on pocket gophers of the genera Geomys and Thomomys; however, little has been published on Pappogeomys, and no investigation of any of these genera has dealt with lipid cycles. Fleharty et al. (1973) summarized data on body composition, lipid cycles, and lipid deposition of four species of rodents in Kansas and attributed differences in lipid cycles among those rodents to historic and evolutionary factors. The purposes of this study were to elucidate lipid cycles and body composition for the two species of pock

The nesting ecology of the Eastern Phoebe and Say's (Sayornis phoebe and S. saya, respectively) was compared during the 1973 and 1974 breeding seasons to determine the factor (s) that might limit their distribution in a sympatric area in west-central Kansas. The study area, Ellis County, includes the extreme breeding range for both species. Overall density of Eastern Phoebes is low (one pair per 26,000 acres) because of a paucity of riparian woodland. Results of field observation and censusing suggest that the density of Say's Phoebes is comparable to that of Eastern Phoebes. Eastern Phoebes were restricted to bridges in riparian areas; Say's Phoebes selected a variety of structures as nest sites throughout open rangeland and farm land in this area. Only one pair of phoebes occupied a given nest site; therefore, they are obviously territorial. Because foraging areas did not overlap, inter-specific hostility resulted in competition for nest sites (bridges) in intermediate habitat. However, densities were low and territorial or competitive interactions were rare events. This study suggests that for the Eastern Phoebe, the only obvious factor limiting the breeding range to the west was a decrease in suitable habitat; competition, as a limiting factor, seems to be of little importance. It appears that the same is true to the east for the Say’s Phoebe.

Herbage dynamics of three plant communities were estimated from June, 1971, to May, 1972, on a Mixed Prairie grassland in Trego County, Kansas. Specific functional attributes estimated were: (1) net primary production, (2) productivity rates, and (3) standing crops of mulch. The relationships of available soil moisture to net primary production was assessed. The three communities sampled were Andropogon gerardi, Bouteloua gracilis-Buchloe dactyloides, and Bouteloua curtipendula-Bouteloua gracilis. Net primary production for these three communities was estimated at 430, 238, and 257 g/m2, respectively. Forbs contributed 45% of the estimate of net primary production (257 g/m2) in the Bouteloua curtipendula-Bouteloua gracilis community. In the Andropogon gerardi community, daily productivity rates for Andropogon gerardi were relatively stable from June to August, 1971, whereas rates for total green herbage increased during the same period. Rate of production for Bouteloua gracilis plus Buchloe dactyloides in the Bouteloua gracilis-Buchloe dactyloides community was highest in August, 1971. Bromus japonicas was the only major cool season species of grass in this community and reached its peak standing crop and highest productivity rate in May, 1972. Mulch was the dominant biomass component in all three communities and levels remained relatively constant during the sample period.

The King, Sora, and Virginia Rails were studied at the Cheyenne Bottoms Waterfowl Management Area in Barton County, Kansas in 1974. An auditory index of these three rail populations was attempted with the use of tape-recorded calls. It is believed that the auditory index technique can be applied to breeding Virginia Rail populations. Because of a paucity of responses, no conclusions could be made as to the suitability of such a technique for use on King Rail and Sora populations. To further investigate rail movements, rails were trapped from 6 June to 10 October. A total of 39 King Rails, three Soras, and 225 Virginia Rails was trapped and banded. Conservative population estimates of the King and Virginia Rail populations were made. Adult King Rails were estimated to number between 20 and 40 pairs and adult Virginia Rails between 200 and 400 pairs. Nesting observations were made on a total of three King Rail nests, one Virginia Rail nest, and one Sora nest. Percentage composition of plant species was determined for each study area. A notation of plant species and depth of water was made for each individual rail observation (both visual and auditory) in an effort to determine habitat preferences.

The purpose of this study was to inventory the ecological status of Lake Atwood, near Atwood, Kansas, and to formulate a feasible renovation plan to restore the lake to a more balanced ecological state. Results of the study indicate that it is economically feasible to renovate Lake Atwood and to create a Waterfowl Refuge, a Prairie Park and a Nature Trail Area adjacent to the Lake. The total estimated cost for the project is $681,000.

The objectives of this study were threefold: 1) to determine whether buntings prefer cultivated areas or native grassland for nest sites; 2) to determine whether nests destroyed by agricultural practices result in renesting in "safer" habitats (such as grassland); and 3) to elucidate the life history of this species near the periphery of its breeding range. Preferred nesting habitat was milo stubble (grain sorghum), with 54 of 83 nests (65.1%), followed by native prairie (20.5%), alfalfa (8.4%), and planted grass (6.0%). Clutch size (70 nests) averaged 4.8 eggs per nest. Females did most (84.3%) of the incubation. Overall nesting success was low (20.5%), and was highest in alfalfa, followed by native prairie, milo stubble, and planted grass. Preparation of fields for planting, predation, and human disturbance were major reasons for nest failures. Productivity was highest in alfalfa, followed by milo stubble, native prairie, and planted grass. Cowbird parasitism occurred in 20.8 per cent of the nests used for analysis. Only one nest was successful and no cowbirds fledged. Parasitism rates were slightly greater in stubble than in grassland. Local abundance fell below the 7-year recorded average. Attempts to correlate abundance with precipitation totals proved inconclusive. No evidence of renesting was found.

Brown-headed Cowbirds were studied in Ellis County, Kansas from February, 1973 to August, 1974. Objectives of the study were to 1) determine the frequency and effect of cowbird parasitism in a prairie habitat 2) determine adaptations of host species to parasitism and, 3) determine population structure and movements of cowbirds banded in Ellis County. One hundred and eleven of 520 nests of host species (21%) were parasitized. The frequency of parasitism varied from a low of 2.7 per cent (Say's Phoebe) to a high of 100 per cent (Cardinal). All but one grassland host species received moderate to heavy parasitism. Parasitized nests fledged one less host (.5 per nest) than non-parasitized nests (1.5 per nest). Only .3 cowbirds fledged per nest. Probable adaptations to parasitism were nesting prior to the cowbirds breeding season by Horned Larks, aggression by colonies of Red-winged Blackbirds, and nest desertion and removal of cowbird eggs by Lark Buntings. A total of 9,651 cowbirds were banded during this study. Adults departed from Ellis County by mid-August, whereas transient populations of immatures were present until November. Observations of color-marked individuals were reported near Buffalo, Oklahoma, Dodge City, Rush Center, and McCracken, Kansas.

The nesting ecology of the Eastern Phoebe and Say's (Sayornis phoebe and S. saya, respectively) was compared during the 1973 and 1974 breeding seasons to determine the factor (s) that might limit their distribution in a sympatric area in west-central Kansas. The study area, Ellis County, includes the extreme breeding range for both species. Overall density of Eastern Phoebes is low (one pair per 26,000 acres) because of a paucity of riparian woodland. Results of field observation and censusing suggest that the density of Say's Phoebes is comparable to that of Eastern Phoebes. Eastern Phoebes were restricted to bridges in riparian areas; Say's Phoebes selected a variety of structures as nest sites throughout open rangeland and farm land in this area. Only one pair of phoebes occupied a given nest site; therefore, they are obviously territorial. Because foraging areas did not overlap, inter-specific hostility resulted in competition for nest sites (bridges) in intermediate habitat. However, densities were low and territorial or competitive interactions were rare events. This study suggests that for the Eastern Phoebe, the only obvious factor limiting the breeding range to the west was a decrease in suitable habitat; competition, as a limiting factor, seems to be of little importance. It appears that the same is true to the east for the Say’s Phoebe.

Analyses of morphological and mensural variation in the molar dentitions of several populations of Microtus pennsylvanicus inhabiting mainland, peninsular, archipelagic, and insular environments in southern New England enabled elucidation of recent evolutionary trends in those populations. Dental evolution in voles of the pennsylvanicus lineage of the genus Microtus generally proceeds toward increased occlusal complexity in mainland habitats but toward decreased occlusal complexity on islands. Intraspecific and interspecific interactions play important roles in determining dental complexity. Quantitatively, insular populations usually are more variable than mainland populations because of the more intense selective forces that exist in insular environments. Likewise, intense K-selection on islands, as compared with that on the mainland, is responsible for the fact that microtine rodents generally are larger on islands than on the adjacent mainland. Factors responsible for increased natural selection on islands are discussed, and analysis of intrapopulational variation is shown to be useful as a measure of the rate of evolution.

Ecological parameters for white-footed mice (Peromyscus leucopus) were estimated from data collected by live-trapping in a riparian habitat in west-central Kansas from October of 1972 through September of 1973. The distribution of white-footed mice on the study area was irregular, and revealed a definite preference for a wooded habitat dominated by American elm (Ulmus americana), box elder (Acer negundo), green ash (Fraxinus pennsylvanica), and honey locust (Gleditsia triacanthos) . Lowest crude densities (7.2/ha) were recorded for late spring and early summer and the highest (40.5/ha) during autumn (October). Ecological densities fluctuated from a summer low of 0/ha in less preferred habitats to autumn (October, 1972) and summer (July, 1973) highs of 124/ha and 111/ha, respectively, in the preferred habitat. Home ranges of males (0.07 +/- 0.03 ha) and females (0.03 +/- 0.01 ha) did not differ significantly. Greatest distances traveled by males did not differ significantly from those of females although a few males traversed more than 100 m in 24 hours during the summer. Population turnover was 35% complete after the first month and 99% complete after only six months. During the study, 37 males and 37 females were on the study area an average of 74 and 82 days, respectively. Biannual peaks in population density occurred after the breeding periods in early autumn (September) and summer (June). The September and June cohorts each produced 31% of the total newborn young. Rates of individual and biomass turnover were 5.94 and 2.01 times per year, respectively. Secondary productivity varied from a low of 0.004g/ha/day in December to a high of 7.1/g/ha/day in June. The white-footed mouse (Peromyscus leucopus) has an extensive geographic distribution in the western hemisphere (Hall and Kelson, 1959). Kansas is at the western periphery of the range of the species; P. leucopus occurs throughout the state except in four western counties (Fleharty and Stadel, 1968). Absence of

Four thirteen-lined ground squirrels (Spermophilus tridecemlineatus) were trained on a DRL 20-sec schedule and given the opportunity to emit a mediating behavior (i.e., running in an activity wheel or manipulating a cork ball attached to a switch). All of the subjects used the manipulanda provided, allowing quantification of the mediating behavior. Results indicated that the number of mediating responses were correlated with the length of interresponse time (IRT) for all animals, and that similarities in the two mediating response data were present. These results are consistent with the theory that mediating behavior facilitates performance on a differential reinforcement of low response rates (DRL) schedule.

The purpose of this study was to inventory the ecological status of Lake Atwood, near Atwood, Kansas, and to formulate a feasible renovation plan to restore the lake to a more balanced ecological state. Results of the study indicate that it is economically feasible to renovate Lake Atwood and to create a Waterfowl Refuge, a Prairie Park and a Nature Trail Area adjacent to the Lake. The total estimated cost for the project is $681,000.

Herbage dynamics of three plant communities were estimated from June, 1971, to May, 1972, on a Mixed Prairie grassland in Trego County, Kansas. Specific functional attributes estimated were: (1) net primary production, (2) productivity rates, and (3) standing crops of mulch. The relationships of available soil moisture to net primary production was assessed. The three communities sampled were Andropogon gerardi, Bouteloua gracilis-Buchloe dactyloides, and Bouteloua curtipendula-Bouteloua gracilis. Net primary production for these three communities was estimated at 430, 238, and 257 g/m2, respectively. Forbs contributed 45% of the estimate of net primary production (257 g/m2) in the Bouteloua curtipendula-Bouteloua gracilis community. In the Andropogon gerardi community, daily productivity rates for Andropogon gerardi were relatively stable from June to August, 1971, whereas rates for total green herbage increased during the same period. Rate of production for Bouteloua gracilis plus Buchloe dactyloides in the Bouteloua gracilis-Buchloe dactyloides community was highest in August, 1971. Bromus japonicas was the only major cool season species of grass in this community and reached its peak standing crop and highest productivity rate in May, 1972. Mulch was the dominant biomass component in all three communities and levels remained relatively constant during the sample period.

The objectives of this study were threefold: 1) to determine whether buntings prefer cultivated areas or native grassland for nest sites; 2) to determine whether nests destroyed by agricultural practices result in renesting in "safer" habitats (such as grassland); and 3) to elucidate the life history of this species near the periphery of its breeding range. Preferred nesting habitat was milo stubble (grain sorghum), with 54 of 83 nests (65.1%), followed by native prairie (20.5%), alfalfa (8.4%), and planted grass (6.0%). Clutch size (70 nests) averaged 4.8 eggs per nest. Females did most (84.3%) of the incubation. Overall nesting success was low (20.5%), and was highest in alfalfa, followed by native prairie, milo stubble, and planted grass. Preparation of fields for planting, predation, and human disturbance were major reasons for nest failures. Productivity was highest in alfalfa, followed by milo stubble, native prairie, and planted grass. Cowbird parasitism occurred in 20.8 per cent of the nests used for analysis. Only one nest was successful and no cowbirds fledged. Parasitism rates were slightly greater in stubble than in grassland. Local abundance fell below the 7-year recorded average. Attempts to correlate abundance with precipitation totals proved inconclusive. No evidence of renesting was found.

The King, Sora, and Virginia Rails were studied at the Cheyenne Bottoms Waterfowl Management Area in Barton County, Kansas in 1974. An auditory index of these three rail populations was attempted with the use of tape-recorded calls. It is believed that the auditory index technique can be applied to breeding Virginia Rail populations. Because of a paucity of responses, no conclusions could be made as to the suitability of such a technique for use on King Rail and Sora populations. To further investigate rail movements, rails were trapped from 6 June to 10 October. A total of 39 King Rails, three Soras, and 225 Virginia Rails was trapped and banded. Conservative population estimates of the King and Virginia Rail populations were made. Adult King Rails were estimated to number between 20 and 40 pairs and adult Virginia Rails between 200 and 400 pairs. Nesting observations were made on a total of three King Rail nests, one Virginia Rail nest, and one Sora nest. Percentage composition of plant species was determined for each study area. A notation of plant species and depth of water was made for each individual rail observation (both visual and auditory) in an effort to determine habitat preferences.

Body composition, energy content, basic weight, and lipid cycles were determined for populations of the plains pocket gopher (Geomys bursarius) and the yellow-faced pocket gopher (Pappogeomys castanops) in Kansas. Lipid content calculated as a percentage of dry body weight varied from 11.35 to 32.20 per cent in G. bursarius and from 14.61 to 30.04 in P. castanops. Seasonal means for energy content ranged from 1.29 to 1.57 kcal/g live weight for G. bursarius and from 1.38 to 1.62 for P. castanops. Per cent ash and water varied from 17.55 to 18.64 and from 67.13 to 72.59, respectively. In both males and females of G. bursarius, basic weight increased from autumn until winter, whereas in males of P. castanops basic weight decreased from summer until winter but in females basic weight decreased only from autumn until winter. Values for per cent lipids dry body weight, per cent lipids live body weight, and kilocalories per gram biomass were significantly lower for subadult P. castanops than adult P. castanops during the summer but per cent water was significantly higher. Seasonal lipid cycles were similar in the two species, with the low in early or middle summer and the high in late winter or early spring. It is postulated that lipid cycles of pocket gophers are the result of energetically expensive activities associated with breeding and burrowing. Numerous ecological studies (Downhower and Hall, 1966; Ingles, 1952; Miller, 1964; Wilks, 1963) have been conducted on pocket gophers of the genera Geomys and Thomomys; however, little has been published on Pappogeomys, and no investigation of any of these genera has dealt with lipid cycles. Fleharty et al. (1973) summarized data on body composition, lipid cycles, and lipid deposition of four species of rodents in Kansas and attributed differences in lipid cycles among those rodents to historic and evolutionary factors. The purposes of this study were to elucidate lipid cycles and body composition for the two species of pock

Analyses of morphological and mensural variation in the molar dentitions of several populations of Microtus pennsylvanicus inhabiting mainland, peninsular, archipelagic, and insular environments in southern New England enabled elucidation of recent evolutionary trends in those populations. Dental evolution in voles of the pennsylvanicus lineage of the genus Microtus generally proceeds toward increased occlusal complexity in mainland habitats but toward decreased occlusal complexity on islands. Intraspecific and interspecific interactions play important roles in determining dental complexity. Quantitatively, insular populations usually are more variable than mainland populations because of the more intense selective forces that exist in insular environments. Likewise, intense K-selection on islands, as compared with that on the mainland, is responsible for the fact that microtine rodents generally are larger on islands than on the adjacent mainland. Factors responsible for increased natural selection on islands are discussed, and analysis of intrapopulational variation is shown to be useful as a measure of the rate of evolution.

Brown-headed Cowbirds were studied in Ellis County, Kansas from February, 1973 to August, 1974. Objectives of the study were to 1) determine the frequency and effect of cowbird parasitism in a prairie habitat 2) determine adaptations of host species to parasitism and, 3) determine population structure and movements of cowbirds banded in Ellis County. One hundred and eleven of 520 nests of host species (21%) were parasitized. The frequency of parasitism varied from a low of 2.7 per cent (Say's Phoebe) to a high of 100 per cent (Cardinal). All but one grassland host species received moderate to heavy parasitism. Parasitized nests fledged one less host (.5 per nest) than non-parasitized nests (1.5 per nest). Only .3 cowbirds fledged per nest. Probable adaptations to parasitism were nesting prior to the cowbirds breeding season by Horned Larks, aggression by colonies of Red-winged Blackbirds, and nest desertion and removal of cowbird eggs by Lark Buntings. A total of 9,651 cowbirds were banded during this study. Adults departed from Ellis County by mid-August, whereas transient populations of immatures were present until November. Observations of color-marked individuals were reported near Buffalo, Oklahoma, Dodge City, Rush Center, and McCracken, Kansas.