Coupling between the lower and upper atmosphere, combined with loss of gas from the upper atmosphere to space, likely contributed to the thin, cold, dry atmosphere of modern Mars. To help understand ongoing ion loss to space, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft made comprehensive measurements of the Mars upper atmosphere, ionosphere, and interactions with the Sun and solar wind during an interplanetary coronal mass ejection impact in March 2015. Responses include changes in the bow shock and magnetosheath, formation of widespread diffuse aurora, and enhancement of pick-up ions. Observations and models both show an enhancement in escape rate of ions to space during the event. Ion loss during solar events early in Mars history may have been a major contributor to the long-term evolution of the Mars atmosphere.

We revised distribution maps of potential presettlement habitat and current populations for Greater Sage-Grouse (Centrocercus urophasianus) and Gunnison Sage- Grouse (C. minimus) in North America. The revised map of potential presettlement habitat included some areas omitted from previously published maps such as the San Luis Valley of Colorado and Jackson area of Wyoming. Areas excluded from the revised maps were those dominated by barren, alpine, and forest habitats. The resulting presettlement distribution of potential habitat for Greater Sage-Grouse encompassed 1 200 483 km2, with the species' current range 668 412 km2. The distribution of potential Gunnison Sage-Grouse habitat encompassed 46 521 km2, with the current range 4787 km2. The dramatic differences between the potential presettlement and current distributions appear related to habitat alteration and degradation, including the adverse effects of cultivation, fragmentation, reduction of sagebrush and native herbaceous cover, development, introduction and expansion of invasive plant species, encroachment by trees, and issues related to livestock grazing. Distribución de Centrocercus spp. en América del Norte Resumen. Revisamos los mapas de distribución potencial precolombino y de poblaciones actuales de Centrocerus urophasianus y C. minimus en América del Norte. El mapa modificado de hábitat potencial precolombino incluyó algunas áreas omitidas de mapas anteriormente publicados, como el Valle San Luis de Colorado y el área de Jackson, Wyoming. Las áreas excluídas de los mapas modificados fueron las dominadas por hábitats forestales, alpinos y estériles. La distribución precolombina resultante para C. urophasianus abarcó 1 200 483 km2, con un territorio actual de 668 412 km2. La distribución de habitat potencial para C. minimus abarcó 46 521 km2, con un territorio actual de 4787 km2. Estos contrastes tan marcados parecen estar relacionados con la modificación y degradación del hábitat, incluyendo los efectos nocivos de la agricultura, la fragmentación de hábitat, la disminución de Artemisia spp. y otras coberturas herbáceas nativas, el desarollo, la introducción y la expansión de especies de plantas invasoras, la invasión de árboles y cuestiones relacionadas con pastoreo de ganado.

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Translocations of greater sage‐grouse (Centrocercus urophasianus) have been attempted in 7 states and one Canadian province with very little success. To recover a small remnant population and test the efficacy of sage‐grouse translocations, we captured and transported 137 adult female sage‐grouse from 2 source populations to a release site in Strawberry Valley, Utah, USA, during March‐April 2003–2005. The resident population of sage‐grouse in Strawberry Valley was approximately 150 breeding birds prior to the release. We radiomarked each female and documented survival, movements, reproductive effort, flocking with resident grouse, and lek attendance. We used Program MARK to calculate annual survival of translocated females in the first year after release, which averaged 0.60 (95% CI = 0.515‐0.681). Movements of translocated females were within current and historic sage‐grouse habitat in Strawberry Valley, and we detected no grouse outside of the study area. Nesting propensity for first (newly translocated) and second (surviving) year females was 39% and 73%, respectively. Observed nest success of all translocated females during the study was 67%. By the end of their first year in Strawberry Valley, 100% of the living translocated sage‐grouse were in flocks with resident sage‐grouse. The translocated grouse attended the same lek as the birds with which they were grouped. In 2006, the peak male count for the only remaining active lek in Strawberry Valley was almost 4 times (135 M) the 6‐year pretranslocation (1998–2003) average peak attendance of 36 males (range 24–50 M). Translocations can be an effective management tool to increase small populations of greater sage‐grouse when conducted during the breeding season and before target populations have been extirpated.

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