Discussant\u27s response to \u27Under the spreading chestnut tree,\u27 accountants\u27 legal liability -- A historical perspective

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Multiple Paternity in a Territorial Passerine: The Bobolink

Electrophoretic and behavioral evidence corroborate the conclusion that Bobolink (Dolichonyx oryzivorus) females occasionally copulate with more than one male, which results in the insemination of a single clutch of eggs by those males. In 2 of 12 families from which blood samples were obtained from the mother, the putative father, and the nestlings, at least 2 males were responsible for fertilization of the clutch. We believe this is only the second bird species in which multiple paternity has been documented conclusively in the wild. Our speculation that it may not be uncommon leads to a caution for evolutionary biologists who use apparent reproductive success in birds to address questions about fitness

Responses of Nesting Bobolinks (Dolichonyx oryzivorus) to Habitat Edges

ABSTRACT.-Avoidance of habitat edges may be contributing to reduced densities of grassland birds in small habitat patches. Nest densities for grassland-nesting Bobolinks (Dolichonyx oryzivorus) were much lower than expected within 25m of forest edges at three sites in New York, and that pattern ( edge avoidance ) extended to 100m at one site. Nests located within 50 m of forest or wooded hedgerow edges had lower daily survival rates, compared with nests \u3e100m from any habitat edge. Bobolinks tended to move away from forest edges when renesting after nest failure; that pattern was especially evident in females that placed their first nest within 50 m of a forest or wooded hedgerow edge. Second nests of all seven of those females were farther from that edge type than their first nests. However, nest placement in relation to wooded edges did not vary significantly between years for those philopatric females nesting at our study sites for more than one year. Bobolinks also avoided nesting near road edges, even though nest survival rates were not lower near that edge type. However, Bobolinks did not appear to avoid nesting near edges adjacent to old fields or pastures. Nest survival near those edge types was higher than near wooded edges and similar to or higher than survival of nests \u3e100m from any edge. Thus, responses of Bobolinks to habitat edges were inconsistent, and nest success was dependent on type of edge

The Effects of Site Quality on Breeding-Site Fidelity in Bobolinks

We compared breeding-site fidelity of Bobolinks (Dolichonyx oryzivorus) at two low-quality sites (Bald Hill and Shackelton Point, BH +SP) with that at one high-quality site (Moore Road, MR) in central New York. Yearly density of fledglings at Moore Road was more than six times the density at Bald Hill and Shackelton Point. Furthermore, individual residents fledged 50-70% more young at the high-quality site. At Moore Road, 70% of the males and 49% of the females returned one or more times, compared with 44% of the males and 25% of the females at the low-quality sites. Successful residents (i.e. those fledging one or more young the previous year) were equally likely to return at all sites. However, the return rates of unsuccessful residents were more than three times higher at the high-quality site. Neither overall return rates nor intrasite dispersal of returning residents differed between individuals that had been successful or unsuccessful the previous year at the high-quality site. At the low-quality sites, individuals unsuccessful the previous year were much less likely to return than were successful individuals (55% vs. 19% for males, 41% vs. 9% for females). Those unsuccessful individuals that did return tended to move farther between nest sites than successful individuals. Overall, site productivity was the best predictor of yearly, site-specific return rates. For females (but not for males), individuals that were resident in one or more years previous were more likely to return than were novice residents (47% vs. 20%). Individuals that had nests experimentally destroyed by hay-cropping returned at similar rates to those of naturally unsuccessful residents. We believe that the patterns of breeding-site fidelity in Bobolinks are primarily the result of experience-based choices by the birds and do not simply reflect patterns of mortality. Bobolinks appear to use both their own reproductive success and that of others at their site to influence their decision to return to a breeding site

Responses of Nesting Bobolinks (Dolichonyx oryzivorus) to Habitat Edges

ABSTRACT.-Avoidance of habitat edges may be contributing to reduced densities of grassland birds in small habitat patches. Nest densities for grassland-nesting Bobolinks (Dolichonyx oryzivorus) were much lower than expected within 25m of forest edges at three sites in New York, and that pattern ( edge avoidance ) extended to 100m at one site. Nests located within 50 m of forest or wooded hedgerow edges had lower daily survival rates, compared with nests \u3e100m from any habitat edge. Bobolinks tended to move away from forest edges when renesting after nest failure; that pattern was especially evident in females that placed their first nest within 50 m of a forest or wooded hedgerow edge. Second nests of all seven of those females were farther from that edge type than their first nests. However, nest placement in relation to wooded edges did not vary significantly between years for those philopatric females nesting at our study sites for more than one year. Bobolinks also avoided nesting near road edges, even though nest survival rates were not lower near that edge type. However, Bobolinks did not appear to avoid nesting near edges adjacent to old fields or pastures. Nest survival near those edge types was higher than near wooded edges and similar to or higher than survival of nests \u3e100m from any edge. Thus, responses of Bobolinks to habitat edges were inconsistent, and nest success was dependent on type of edge

Public Tolerance of a Suburban Deer Herd: Implications for Control

Suburban deer populations have been increasing in the eastern U.S., resulting in deer-human conflicts that can not always be resolved by a traditional management approach. Professionals responsible for management of deer damage (herd control and extension education) need information on the extent and nature of deer damage in suburban situations. Attitudes of suburban residential property owners about wildlife in general and deer in particular must be identified so that control measures that are socially acceptable as well as biologically feasible can be formulated. People\u27s tolerance of deer damage and their propensity for undertaking on-site preventive measures need to be analyzed. Residents of Islip (Long Island), New York who live in the vicinity of the Seatuck National Wildlife Refuge were surveyed in spring 1985 to determine their experiences with Refuge deer. Damage to ornamental plants totalled $28,000 for the preceding year, but people generally enjoyed having deer in their neighborhood, and tolerated considerable damage. They were more concerned with the potential for transmission of Lyme disease by deer. Residents were generally in agreement with the concept of managing wildlife as a renewable resource, but they generally opposed sport or meat hunting, which might present a potential barrier to herd control. Most residents did not want a herd reduction, but this situation could change if the deer population were to increase substantially or if deer are found to be a key link in transmission of Lyme disease to humans. Implications of these findings are discussed relative to deer herd control and extension education, which might serve as complementary components of a program directed at alleviating deer damage

PUBLIC TOLERANCE OF A SUBURBAN DEER HERD: IMPLICATIONS FOR CONTROL

Suburban deer populations have been increasing in the eastern U.S., resulting in deer-human conflicts that can not always be resolved by a traditional management approach., Professionals responsible for management of deer damage (herd control and extension education) need information on the extent and nature of deer damage in suburban situations. Attitudes of suburban residential property owners about wildlife in general and deer in particular must be identified so that control measures that are socially acceptable as well as biologically feasible can be formulated o People\u27s tolerance of deer damage and their propensity for undertaking on-site preventive measures need to be analyzed. Residents of Islip (Long Island), New York who live in the vicinity of the Seatuck National Wildlife Refuge were surveyed in spring 1985 to determine their experiences with Refuge deer. Damage to ornamental plants totaled $28,000 for the preceding year, but people generally enjoyed having deer in their neighborhood, and tolerated considerable damage. They were more concerned with the potential for transmission of Lyrae disease by deer. Residents were generally in agreement with the concept of managing wildlife as a renewable resource, but they generally opposed sport or meat hunting, which might present a potential barrier to herd control. Most residents did not want a herd reduction, but this situation could change if the deer population were to increase substantially or if deer are found to be a key link in transmission of Lyme disease to humans. Implications of these findings are discussed relative to deer herd control and extension education, which might serve as complementary components of a program directed at alleviating deer damage

Multiple Paternity in a Territorial Passerine: The Bobolink

Electrophoretic and behavioral evidence corroborate the conclusion that Bobolink (Dolichonyx oryzivorus) females occasionally copulate with more than one male, which results in the insemination of a single clutch of eggs by those males. In 2 of 12 families from which blood samples were obtained from the mother, the putative father, and the nestlings, at least 2 males were responsible for fertilization of the clutch. We believe this is only the second bird species in which multiple paternity has been documented conclusively in the wild. Our speculation that it may not be uncommon leads to a caution for evolutionary biologists who use apparent reproductive success in birds to address questions about fitness

Dispersal of protoplanetary discs: How stellar properties and the local environment determine the pathway of evolution

We study the evolution and final dispersal of protoplanetary discs that evolve under the action of internal and external photoevaporation, and different degrees of viscous transport. We identify five distinct dispersal pathways, which are i) very long lived discs ($>20\,$Myr), ii) inside-out dispersal where internal photoevaporation dominates and opens inner holes, iii) outside-in dispersal where external photoevaporation dominates through disc truncation and two intermediate regimes characterised by lingering material in the inner disc with the outer disc dispersed predominantly by either internal or external photoevaporation. We determine how the lifetime, relative impact of internal and external winds and clearing pathway varies over a wide, plausible, parameter space of stellar/disc/radiation properties. There are a number of implications, for example in high UV environments because the outer disc lifetime is shorter than the time-scale for clearing the inner disc we do not expect transition discs to be common, which appears to be reflected in the location of transition disc populations towards the Orion Nebular Cluster. Irrespective of environment, we find that ongoing star formation is required to reproduce observed disc fractions as a function of stellar cluster age. This work demonstrates the importance of including both internal and external winds for understanding protoplanetary disc evolution.Comment: Submitted to MNRAS. 19 pages, 15 figure

A supertree approach to shorebird phylogeny

BACKGROUND: Order Charadriiformes (shorebirds) is an ideal model group in which to study a wide range of behavioural, ecological and macroevolutionary processes across species. However, comparative studies depend on phylogeny to control for the effects of shared evolutionary history. Although numerous hypotheses have been presented for subsets of the Charadriiformes none to date include all recognised species. Here we use the matrix representation with parsimony method to produce the first fully inclusive supertree of Charadriiformes. We also provide preliminary estimates of ages for all nodes in the tree. RESULTS: Three main lineages are revealed: i) the plovers and allies; ii) the gulls and allies; and iii) the sandpipers and allies. The relative position of these clades is unresolved in the strict consensus tree but a 50% majority-rule consensus tree indicates that the sandpiper clade is sister group to the gulls and allies whilst the plover group is placed at the base of the tree. The overall topology is highly consistent with recent molecular hypotheses of shorebird phylogeny. CONCLUSION: The supertree hypothesis presented herein is (to our knowledge) the only complete phylogenetic hypothesis of all extant shorebirds. Despite concerns over the robustness of supertrees (see Discussion), we believe that it provides a valuable framework for testing numerous evolutionary hypotheses relating to the diversity of behaviour, ecology and life-history of the Charadriiformes