The Hercules-Lyra Association revisited New age estimation and multiplicity study

The Her-Lyr assoc., a nearby young MG, contains a few tens of ZAMS stars of SpT F to M. The existence and the properties of the Her-Lyr assoc. are controversial and discussed in the literature. The present work reassesses properties and the member list of Her-Lyr assoc., based on kinematics and age. Many objects form multiple systems or have low-mass companions and so we need to account for multiplicity. We use our own new imaging obs. and archival data to identify multiple systems. The colors and magnitudes of kinematic candidates are compared to isochrones. We derive further information on the age based on Li depletion, rotation, and coronal and chromospheric activity. A set of canonical members is identified to infer mean properties. Membership criteria are derived from the mean properties and used to discard non-members. The candidates selected from the literature belong to 35 stellar systems, 42.9% of which are multiple. Four multiple systems are confirmed in this work by common proper motion. An orbital solution is presented for the binary system HH Leo B and C. Indeed, a group of candidates displays signatures of youth. 7 canonical members are identified. The distribution of EWLi of canonical Her-Lyr members is spread widely and is similar to that of the Pleiades and the UMa group. Gyrochronology gives an age of 257+-46 Myr which is in between the ages of the Pleiades and the Ursa Major group. The measures of chromospheric and coronal activity support the young age. Four membership criteria are presented based on kinematics, EWLi, chromospheric activity, and gyro. age. In total, 11 stars are identified as certain members including co-moving objects plus additional 23 possible members while 14 candidates are doubtful or can be rejected. A comparison to the mass function, however, indicates the presence of a large number of additional unidentified low-mass members.Comment: 19 pages 16 figure

Economic aspects of wolf recolonization in Utah

An assessment of likely economic effects of wolf recovery should be included in the discussion of the future of wolves in Utah. In this section, we discuss both the potential benefits and the expected costs of wolf recovery to Utah’s economy. The potential benefits include both use—such as increases in tourism resulting from the presence of wolves—or non-use values that can be measured by willingness to pay surveys. The expected costs of recovery include direct costs born by agencies involved in wolf management, livestock owners that experience losses from wolf depredation, and those that might result from reduced game take by hunters. In addition, there may be indirect costs, which are more difficult to quantify

Wolves in Utah: An analysis of potential impacts and recommendations for management

The historic range of gray wolves (Canis lupus) in Utah was essentially statewide. Although their presence cannot be disputed, the historic abundance of wolves in Utah is unknown. The release of gray wolves into Yellowstone National Park and central Idaho in 1995 established growing populations, and increasing dispersal is bringing these wolves closer to Utah. It seems likely that wolves will commingle with Utah\u27s other native mammals in the near future. The potential presence of wolves in Utah is generating a series of questions and debates. In this report, we review the potential of wolves in Utah and make predictions regarding the social and economic impacts of wolf recolonization on the livestock industry, on hunter success, and on wildlife managers, and then make recommendations on possible ways to mitigate these impacts

Biological aspects of wolf recolonization in Utah

Wolves have been one of the most scientifically examined of all wildlife species (Mech, 1995b). Many studies have focused on the effects of wolf reintroductions and recolonization. In this section, we address how wolves may naturally disperse into Utah, highlight areas identified in our habitat model as constituting the most favorable wolf habitat in Utah, estimate potential wolf populations in Utah, and describe what is currently known about the influence of wolves on an ecosystem