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Articles 1861 - 1890 of 2326

Full-Text Articles in Ecology and Evolutionary Biology

Sandhill Crane Nest And Egg Characteristics At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield Jan 2001

Sandhill Crane Nest And Egg Characteristics At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield

Proceedings of the North American Crane Workshop

For the period 1969-89, greater sandhill crane (Grus canadensis tabida) nest and egg characteristics were assessed for pairs on the Malheur National Wildlife Refuge (Malheur), Oregon. Nests mostly were in broad-fruited burreed (Sparganium eurycarpum) and hardstem bulrush (Scirpus acutus) and were constructed primarily of the same vegetative species that surrounded nests. Averages for nest parameters were diameter 127 xIII cm, crown diameter 77 x 69 cm, bowl diameter 41 x 37 em, bowl depth 5.8 em, nest height 12.4 em, and water depth 25.8 cm. Nests were placed in vegetation with a mean height …


Effects Of An Early Spring Burn On Greater Sandhill Crane Nesting Success At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield, John E. Cornely, Bradley D. Ehlers Jan 2001

Effects Of An Early Spring Burn On Greater Sandhill Crane Nesting Success At Malheur National Wildlife Refuge, Oregon, Carroll D. Littlefield, John E. Cornely, Bradley D. Ehlers

Proceedings of the North American Crane Workshop

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 …


Evaluation Of The Major Histocompatibility Complex (Mhc) In Cranes: Applications To Conservation Efforts, Susan I. Jarvi, Marcia M. Miller, Ronald M. Gotol, George F. Gee, W. Elwood Briles Jan 2001

Evaluation Of The Major Histocompatibility Complex (Mhc) In Cranes: Applications To Conservation Efforts, Susan I. Jarvi, Marcia M. Miller, Ronald M. Gotol, George F. Gee, W. Elwood Briles

Proceedings of the North American Crane Workshop

Although there have been heated discussions concerning the relative importance of using Mhc diversity as a basis for selecting breeders in conservation projects, most parties agree that the genetic variability residual in an endangered species should be maintained through genetic management, if at all possible. Substantial evidence exists (particularly in birds) documenting the influences of specific Mhc haplotypes on disease outcome and also that those individuals which are heterozygous for Mhc alleles appear to have an advantage for survival over those that are homozygous. Thus, conservation of genetic variability of the Mhc is likely important for the preservation of fitness, …


Distribution, Abundance, And Reproduction Of The Cuban Sandhill Crane (Grus Canadensis Nesiotes), Xiomara Galvez Aguilera, Vicente Berovides Alvarez, Jose Rivera Rosales Jan 2001

Distribution, Abundance, And Reproduction Of The Cuban Sandhill Crane (Grus Canadensis Nesiotes), Xiomara Galvez Aguilera, Vicente Berovides Alvarez, Jose Rivera Rosales

Proceedings of the North American Crane Workshop

We discuss the distribution, abundance, and reproduction of the Cuban sandhill crane (Grus canadensis nesiotes). This is an overview of a 5-year study conducted by the National Organization for the Protection of Flora and Fauna of the Ministry of Agriculture for the Republic of Cuba and assisted by the International Crane Foundation and Brehm Fund. The distribution of this subspecies was determined by visiting potential sites and areas where this race has previously been reported. Nine new populations were found. This brings the total to 11 on the Isle of Cuba, 1 on Cayo Romano, and 2 on …


Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding Jan 2001

Interactions Of Sandhill Cranes And Whooping Cranes With Foreign Objects In Florida, Martin J. Folk, Stephen A. Nesbitt, Marilyn G. Spalding

Proceedings of the North American Crane Workshop

During studies of Florida sandhill cranes (Grus canadensis pralensis), greater sandhill cranes (G. c. tabida), and whooping cranes (G. americana) in Florida, we documented cases where these birds were in contact with human-produced objects that resulted in injury or death. We describe >40 instances in which cranes collided with powerlines or fences, became entangled in string or fishing line, or ingested foreign objects. The effect of human-produced objects on crane populations, particularly small populations, may be significant.


Way-Finding And Landmarks: The Multiple Bearings Hypothesis, Alan C. Kamil, Ken Cheng Jan 2001

Way-Finding And Landmarks: The Multiple Bearings Hypothesis, Alan C. Kamil, Ken Cheng

Papers in Behavior in Biological Sciences

Clark’s nutcrackers (Nucifraga columbiana) are capable of very precise searching using the metric relationships between a goal and multiple landmarks to relocate the goal location. They can judge the direction more accurately than the distance to a landmark when the landmark is distant from the goal. On the basis of these findings, we propose that nutcrackers use a set of bearings, each a measure of the direction from the goal to a different landmark, when searching for that goal. The results of a simulation demonstrate that increasing the number of landmarks used results in increasingly precise searching. This …


Review Of Evolution And Cognition, Edited By Cecilia Heyes And Ludwig Huber., Alan Kamil Jan 2001

Review Of Evolution And Cognition, Edited By Cecilia Heyes And Ludwig Huber., Alan Kamil

Papers in Behavior in Biological Sciences

Heyes and Huber have edited a volume that surveys much of the current research into cognition in animals, reflecting the strengths and weaknesses of this field. The book is divided into five sections. In the first part, titled “Orientations,” four authors lay out their basic general views of the field. The first two chapters in this section are by the editors. First, Heyes makes the case for an approach to evolutionary psychology that she labels “in the round,” an approach that would encompass studies of human and nonhuman animals alike and include a broad range of contemporary evolutionary approaches. This …


Managing Minnesota's Recovered Wolves, L. David Mech Jan 2001

Managing Minnesota's Recovered Wolves, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The Minnesota wolf (Canis lupus) population was estimated by the Minnesota Department of Natural Resources at 2,450 during winter 1997-1998 and had increased at an average annual rate of 4.5°% since winter 1988-1989. The population may be removed from the federal endangered species list by 2002, and management would then return to the state. A federal recovery team recommended a population goal of 1,250-1,400 wolves for Minnesota, with none in the agricultural region. A plan approved by the Minnesota legislature, however, continues the protection of wolves, except for pet and livestock depredation control, for at least 5 years …


Electrophysiological Studies Of Olfaction In The Whip Spider Phrynus Parvulus (Arachnida, Amblypygi), Eileen Hebets, Reginald F. Chapman Nov 2000

Electrophysiological Studies Of Olfaction In The Whip Spider Phrynus Parvulus (Arachnida, Amblypygi), Eileen Hebets, Reginald F. Chapman

Eileen Hebets Publications

The olfactory response of the whip spider Phrynus parvulus from Costa Rica was examined using a technique analogous to that used for insect electroantennograms on the tarsi of the antenniform legs which bear multiporous sensilla. Responses to 42 chemicals representing different chain lengths of alkanes, carboxylic acids, alcohols, aldehydes, and ketones, as well as some esters, monoterpenes, and phenolics were examined. Fifty-four percent of the chemicals tested elicited responses. Concentration–response curves were generated for guaiacol, hexanal, methyl salicylate, benzaldehyde, octanoic acid, and linalool. Guaiacol, benzaldehyde, and hexanol elicited the greatest responses and no differences were detected between the sexes. Compounds …


An Analysis Of Migratory Behavior Physiological Condition And Life History Strategy In The Salamanders Ambystoma Mabeei And A. Opacum In Southeastern Virginia, Michael W. Mccoy Oct 2000

An Analysis Of Migratory Behavior Physiological Condition And Life History Strategy In The Salamanders Ambystoma Mabeei And A. Opacum In Southeastern Virginia, Michael W. Mccoy

Biological Sciences Theses & Dissertations

Ambystoma mabeei is listed as threatened in Virginia due to its rarity and susceptibility to urbanization and poor forestry practices. The goal of this study was to identify factors that may affect the persistence of A. mabeei in Virginia by studying the life history and ecology of A. mabeei and its syntopic congener A. opacum. This information will contribute to the knowledge of life history variation within Ambystomatidae and will be critical for the development of a comprehensive management plan for A. mabeei. Population sizes of the two species and the proximate factors responsible for initiating breeding migrations were determined …


Mixing At Young Ages Reduces Fighting In Unacquainted Domestic Pigs, Anton D. Pitts, Daniel M. Weary, Edmond A. Pajor, David Fraser Jun 2000

Mixing At Young Ages Reduces Fighting In Unacquainted Domestic Pigs, Anton D. Pitts, Daniel M. Weary, Edmond A. Pajor, David Fraser

Agonistic Behavior Collection

Under normal farming practices, piglets from different litters are often mixed around the time of weaning, and a high incidence of fighting and minor injuries often occur. The aim of this experiment was to determine the effect of age on the incidence of fighting in piglets mixed before weaning, at different ages between 5 and 26 days. We found no significant relationship between age and the likelihood that a pair of piglets would fight during the first 75 min after mixing. However, the duration of the first fight observed increased from 101±38 s at 5 days to 621±278 s at …


Bubble Ring Play Of Bottlenose Dolphins (Tursiops Truncatus): Implications For Cognition, Brenda Mccowan, Lori Marino, Erik Vance, Leah Walke, Diana Reiss Mar 2000

Bubble Ring Play Of Bottlenose Dolphins (Tursiops Truncatus): Implications For Cognition, Brenda Mccowan, Lori Marino, Erik Vance, Leah Walke, Diana Reiss

Sentience Collection

Research on the cognitive capacities of dolphins and other cetaceans (whales and porpoises) has importance for the study of comparative cognition, particularly with other large-brained social mammals, such as primates. One of the areas in which cetaceans can be compared with primates is that of object manipulation and physical causality, for which there is an abundant body of literature in primates. The authors supplemented qualitative observations with statistical methods to examine playful bouts of underwater bubble ring production and manipulation in 4 juvenile male captive bottlenose dolphins (Tursiops truncatus). The results are consistent with the hypothesis that dolphins monitor the …


Habitat Utilization Of Fish Species On The Ohio River: Preliminary Development Of A Multi-Metric Habitat Index, James P. Hawkes Jan 2000

Habitat Utilization Of Fish Species On The Ohio River: Preliminary Development Of A Multi-Metric Habitat Index, James P. Hawkes

Theses, Dissertations and Capstones

Development of a habitat index requires an understanding of the longitudinal distribution of habitat, fish assemblages, and how the two interact. Because of the complexity and size of the Ohio River, this understanding has not been reached. Habitat analysis has long been considered, and is essential, in assigning impaired and reference condition of habitat quality. The Ohio River is diverse in the distribution of its habitat within pool and river-wide. An Analysis of Variance (ANOVA) was used to analyze these distributions. Within pool assessment of % habitat composition revealed woody cover and vegetation types were significantly greater in the lowest …


The Male-Male Tandem: A Novel Form Of Mate Guarding In Perithemis Tenera, Paul V. Switzer, Jaime K. Schultz Jan 2000

The Male-Male Tandem: A Novel Form Of Mate Guarding In Perithemis Tenera, Paul V. Switzer, Jaime K. Schultz

Faculty Research & Creative Activity

No abstract provided.


Leadership In Wolf, Canis Lupus, Packs, L. David Mech Jan 2000

Leadership In Wolf, Canis Lupus, Packs, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

I examine leadership in Wolf (Callis lupus) packs based on published observations and data gathered during summers from 1986 to 1998 studying a free-ranging pack of Wolves on Ellesmere Island that were habituated to my presence. The breeding male tended to initiate activities associated with foraging and travel, and the breeding female to initiate, and predominate in, pup care and protection. However, there was considerable overlap and interaction during these activities such that leadership could be considered a joint function. In packs with multiple breeders, quantitative information about leadership is needed.


Do Wolves Affect White-Tailed Buck Harvest In Northeastern Minnesota?, L. David Mech, Michael E. Nelson Jan 2000

Do Wolves Affect White-Tailed Buck Harvest In Northeastern Minnesota?, L. David Mech, Michael E. Nelson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

We used simple linear regression to analyze 8-23 years of data on a wolf (Canis lupus) population and human harvest of white-tailed deer (Odocoileus virginianus) bucks in northeastern Minnesota to determine any effects of wolves on buck harvesting. Over the long term, wolves accounted for at least 14-22% inter-year variation in buck harvest in the region, but an unknown amount of variation in hunter effort have obscured any more precise estimate. For part of the area with poorest habitat, we found strong relationships (r2 = 0.66-0.84) between annual wolf numbers and buck harvests from 1988 …


Proximate Constraints On Intruder Detection In The Dragonfly Perithemis Tenera (Odonata: Libellulidae): Effects Of Angle Of Approach And Background, Paul Switzer, Perri Eason Jan 2000

Proximate Constraints On Intruder Detection In The Dragonfly Perithemis Tenera (Odonata: Libellulidae): Effects Of Angle Of Approach And Background, Paul Switzer, Perri Eason

Faculty Research & Creative Activity

The implications of insects’ vision for territorial defense have been relatively little studied in the field. In the dragonfly Perithemis tenera Say we investigated whether either the angle at which an intruder was viewed by a territorial resident or the background against which it was viewed affected the detection of that intruder. Residents detected intruders at a greater distance if the intruders were directly in front of them; they also detected more intruders in front of them than from other angles. Intruders viewed against distant vegetation were detected more readily than were intruders against near vegetation. Residents detected more intruders …


Proximate Constraints On Intruder Detection In The Dragonfly Perithemis Tenera (Odonata: Libellulidae): Effects Of Angle Of Approach And Background, Paul V. Switzer, Perri K. Eason Jan 2000

Proximate Constraints On Intruder Detection In The Dragonfly Perithemis Tenera (Odonata: Libellulidae): Effects Of Angle Of Approach And Background, Paul V. Switzer, Perri K. Eason

Faculty Research & Creative Activity

The implications of insects’ vision for territorial defense have been relatively little studied in the field. In the dragonfly Perithemis tenera Say we investigated whether either the angle at which an intruder was viewed by a territorial resident or the background against which it was viewed affected the detection of that intruder. Residents detected intruders at a greater distance if the intruders were directly in front of them; they also detected more intruders in front of them than from other angles. Intruders viewed against distant vegetation were detected more readily than were intruders against near vegetation. Residents detected more intruders …


The Male-Male Tandem: A Novel Form Of Mate Guarding In Perithemis Tenera, Paul Switzer, Jaime Schultz Jan 2000

The Male-Male Tandem: A Novel Form Of Mate Guarding In Perithemis Tenera, Paul Switzer, Jaime Schultz

Faculty Research & Creative Activity

No abstract provided.


Regulation Of Contact With Offspring By Domestic Sows: Temporal Patterns And Individual Variation, E. A. Pajor, D. L. Kramer, D. Fraser Jan 2000

Regulation Of Contact With Offspring By Domestic Sows: Temporal Patterns And Individual Variation, E. A. Pajor, D. L. Kramer, D. Fraser

Rearing Behavior Collection

We used a sow-controlled housing system to examine temporal and individual variation in the tendency of sows to associate with young. During a 5-week lactation, 22 sows and litters were housed in a pen where the sow could freely leave and re-enter the piglets' area by stepping over a barrier that the piglets could not cross. Despite this option, the sows remained with the piglets almost constantly during the 1st day after birth. Nineteen sows ('leavers') changed to spending most of their time away from the litter at some point in the lactation. The change was rapid, often within a …


Assessing Factors That May Predispose Minnesota Farms To Wolf Depredations On Cattle, L. David Mech, Elizabeth K. Harper, Thomas J. Meier, William J. Paul Jan 2000

Assessing Factors That May Predispose Minnesota Farms To Wolf Depredations On Cattle, L. David Mech, Elizabeth K. Harper, Thomas J. Meier, William J. Paul

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Wolf (Canis lupus) depredations on livestock cause considerable conflict and expense in Minnesota. Furthermore, claims are made that such depredations are fostered by the type of animal husbandry practiced. Thus, we tried to detect factors that might predispose farms in Minnesota to wolf depredations. We compared results of interviews with 41 cattle farmers experiencing chronic cattle losses to wolves (chronic farms) with results from 41 nearby "matched" farms with no wolf losses to determine farm characteristics or husbandry practices that differed and that therefore might have affected wolf depredations. We also used a Geographic Information System (GIS) to …


Geometric Rule Learning By Clark’S Nutcrackers (Nucifraga Columbiana), Alan Kamil, Juli E. Jones Jan 2000

Geometric Rule Learning By Clark’S Nutcrackers (Nucifraga Columbiana), Alan Kamil, Juli E. Jones

Papers in Behavior in Biological Sciences

Clark’s nutcrackers (Nucifraga columbiana) were trained to search in a location defined by its geometric relationship to 2 landmarks. Two groups were trained to search at different points along the line connecting the landmarks, and 2 groups were trained to find the 3rd point of a triangle, on the basis of either direction or distance from the landmarks. All groups learned and transferred to new interlandmark distances. However, the constant-distance group learned more slowly, searched less accurately, and showed less transfer than the other 3 groups. When tested with new orientations of the landmarks, the birds tended to …


The Cost Of Limited Attention In Blue Jays, Reuven Dukas, Alan Kamil Jan 2000

The Cost Of Limited Attention In Blue Jays, Reuven Dukas, Alan Kamil

Papers in Behavior in Biological Sciences

Experiments with fish and birds suggest that animals are unable to simultaneously allocate sufficient attention to tasks such as the detection of an approaching predator while searching for cryptic prey. We quantified the effects of limited attention on performance in controlled laboratory settings and report here the first direct evidence that attending to a difficult central task simulating foraging deters a bird’s ability to detect a peripheral target, which could be a predator. Our results fill a gap between ecological and neurobiological studies by illustrating that, although attention is an efficient filtering mechanism, limited attention may be a major cause …


Surviving The Flood: Plastron Respiration In The Non-Tracheate Arthropod Phrynus Marginemaculatus (Amblypygi: Arachnida), Eileen Hebets, Reginald F. Chapman Jan 2000

Surviving The Flood: Plastron Respiration In The Non-Tracheate Arthropod Phrynus Marginemaculatus (Amblypygi: Arachnida), Eileen Hebets, Reginald F. Chapman

Eileen Hebets Publications

Specimens of Phrynus marginemaculatus can remain responsive when submerged in water for more than 24 hours. Behavioral data indicate that P. marginemaculatus utilizes dissolved oxygen from the surrounding water. Scanning electron miscroscopy and light microscope sections show cuticular modifications for plastron respiration. All previous examples of plastron respiration have involved animals with tracheal systems, but amblypygids respire through the use of two pairs of book lungs. This study provides the first example of plastron respiration not only in the order Amblypygi, but also, in any non-tracheate arthropod.


Leg Ornamentation And The Efficacy Of Courtship Display In Four Species Of Wolf Spider (Araneae: Lycosidae), Eileen Hebets, George W. Uetz Jan 2000

Leg Ornamentation And The Efficacy Of Courtship Display In Four Species Of Wolf Spider (Araneae: Lycosidae), Eileen Hebets, George W. Uetz

Eileen Hebets Publications

This study used both correlative and experimental video playback methods to test the hypothesis that the secondary sexual traits of male wolf spiders act to increase the efficacy of visual courtship displays. Direct observations of courtship of several lycosid genera and a review of the literature revealed a significant association between ornamentation and visual courtship displays. This suggests that the ornamentation may be playing the role of amplifier for a visual display. To test this hypothesis, male courtship behaviors of four Schizocosa species were experimentally manipulated using video-imaging techniques. Females of species with non-visually displaying, non-ornamented males (Schizocosa duplex …


Prolonged Winter Undernutrition And The Interpretation Of Urinary Allantoin:Creatinine Ratios In White-Tailed Deer, Glenn D. Delgiudice, Ken D. Kerr, L. David Mech, Ulysses S. Seal Jan 2000

Prolonged Winter Undernutrition And The Interpretation Of Urinary Allantoin:Creatinine Ratios In White-Tailed Deer, Glenn D. Delgiudice, Ken D. Kerr, L. David Mech, Ulysses S. Seal

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The urinary allantoin:creatinine (A:C) ratio (expressed in micromoles of allantoin to micromoles of creatinine) has shown potential as an index of recent winter energy intake in preliminary controlled studies of elk (Cervus elaphus) involving mild condition deterioration (up to 11% loss of body mass). To ensure reliable nutritional assessments of free-ranging cervids by measuring A:C ratios of urine in snow, it is essential to extend this work. We assessed the effect of moderate and severe winter nutritional restriction on urinary A:C ratios of captive white-tailed deer (Odocoileus virginianus) that lost up to 32% body mass and …


Proximity Of White-Tailed Deer, Odocoileus Virginianus, Ranges To Wolf, Canis Lupus, Pack Homesites, Michael E. Nelson, L. David Mech Jan 2000

Proximity Of White-Tailed Deer, Odocoileus Virginianus, Ranges To Wolf, Canis Lupus, Pack Homesites, Michael E. Nelson, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Seven adult female White-tailed Deer (Odocoileus virginianus) in northeastern Minnesota lived within 1.8 km of Wolf pack (Canis lupus) homesites without vacating their home ranges. Six of these deer and at least three of their fawns survived through the Wolf homesite period.


A Record Large Wolf, Canis Lupus, Pack In Minnesota, L. David Mech Jan 2000

A Record Large Wolf, Canis Lupus, Pack In Minnesota, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

This report documents a pack of 22-23 Wolves (Canis lupus) in central Minnesota. This is larger than the largest pack previously observed on the mainland in the midwestern U.s. during 650 wolf pack-years. Because this record-large pack preyed on White-tailed Deer (Odocoileus virginianus), one of the Wolfs smaller prey, it is evidence that pack size and prey size are not tightly related. It also indicates the size that Wolf packs can attain in the area if fully protected from human persecution.


Lack Of Reproduction In Muskoxen And Arctic Hares Caused By Early Winter?, L. David Mech Jan 2000

Lack Of Reproduction In Muskoxen And Arctic Hares Caused By Early Winter?, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

A lack of young muskoxen (Ovibos moschatus) and arctic hares (Lepus arcticus) in the Eureka area of Ellesmere Island, Northwest Territories (now Nunavut), Canada, was observed during summer 1998, in contrast to most other years since 1986. Evidence of malnourished muskoxen was also found. Early winter weather and a consequent 50% reduction of the 1997 summer replenishment period appeared to be the most likely cause, giving rise to a new hypothesis about conditions that might cause adverse demographic effects in arctic herbivores.

Durant l’été 1998, et ce, à la différence de la plupart des années depuis …


Accuracy And Precision Of Estimating Age Of Gray Wolves By Tooth Wear, Philip S. Gipson, Warren B. Ballard, Ronald M. Nowak, L. David Mech Jan 2000

Accuracy And Precision Of Estimating Age Of Gray Wolves By Tooth Wear, Philip S. Gipson, Warren B. Ballard, Ronald M. Nowak, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

We evaluated the accuracy and precision of tooth wear for aging gray wolves (Canis lupus) from Alaska, Minnesota, and Ontario based on 47 known-age or known-minimum-age skuIIs. Estimates of age using tooth wear and a commercial cementum annuli-aging service were useful for wolves up to 14 years old. The precision of estimates from cementum annuli was greater than estimates from tooth wear, but tooth wear estimates are more applicable in the field. We tended to overestimate age by 1-2 years and occasionaIIy by 3 or 4 years. The commercial service aged young wolves with cementum annuli to within …