: During severe winters, mule deer (Odocoileus hemionus) concentrated on ranges in poor condition can experience high mortality. Winter‐feeding programs have been implemented to mitigate this mortality. We studied effects on body condition, mortality, fawn production, and migration of mule deer following winter‐feeding in the Cache‐Wasatch Mountains of northern Utah, USA. Fed deer exhibited 12% higher live body‐condition indices both years (main effect feed: F1,7.32 = 5.39, P = 0.052), lower mortality (33% vs. 55%: χ21= 4.58, P < 0.05), and produced more fawns (19 fawns:18 fed F vs. 11 fawns:12 nonfed F; t27.2 = 2.20, P < 0.036) than nonfed deer. Fed deer migrated later in spring 2004 (x̄ = 13 Apr) than nonfed deer (x̄ = 24 Mar; t34= 3.25, P = 0.003). Fed deer spent more time on winter range in 2003‐2004 (x̄ = 157 d) than nonfed deer (x̄ = 121 d; t20 = 3.63, P = 0.002), and more time on winter range for both winters combined (fed deer x̄ = 321 d, nonfed deer x̄ = 257 d; t27 = 3.29, P = 0.003). Concomitantly, wildlife managers need to recognize that any possible benefits accrued to mule deer populations in terms of increased nutritional status as a result of winter‐feeding programs may be mitigated by altered timing of migration and increased duration of use of seasonal ranges by fed deer.

Winter-feeding of mule deer (Odocoileus hemionus) in developed landscapes is often advocated by stakeholders to compensate for lost or fragmented winter range. However the reported benefits of winterfeeding mule deer to increase survival and productivity in altered landscapes are mixed. Few studies have examined the long-term effects of winter-feeding on mule deer productivity. We studied the effects of a winter-feeding program conducted in a developed landscape in northern Utah, USA from 2001 to 2006 on the productivity, survival, and mortality of 92 adult female deer (does) that were captured and radiocollared on 4 feed and 4 nonfeed sites. We also evaluated the potential for feeding programs to impact winter-range habitat quality through increased browse utilization. Fawn production (P ¼ 0.36), and survival (P ¼ 0.12) did not differ for fed and nonfed does. Deer-vehicle collisions were the primary cause of mortality for radiocollared deer in both populations (P ¼ 0.97). Utilization of desired browse species was higher on sites where deer were fed (P 0.001), although deer numbers were similar at feed and nonfeed sites. When developing big game winter-feeding policies for developed landscapes, managers must consider the full range of long-term potential population and habitat impacts to include increased anthropogenic-related mortality and increased potential for habitat degradation prior to policy implementation. ß 2011 The Wildlife Society.

We hypothesized that lambs discriminate the postingestive effects of P and associate those effects with feed flavor to modify feed choices. Three predictions were tested based on this hypothesis: 1) lambs will modify preference for arbitrary flavors eaten during intraruminal infusions of NaH2PO4, 2) changes in preferences are more specific than changes in osmotic load induced by salts of Na; and 3) preference for P is inversely related to the concentration of inorganic P in blood. Thirty lambs were depleted of P by the offer of a P-deficient diet, allocated to 3 groups (10 lambs/group), and conditioned during 3 periods as follows: During conditioning period 1, lambs in each of 3 groups ate a poorly nutritious feed (grape pomace), flavored differently for each group, while water was infused into the rumen. During conditioning periods 2 and 3, lambs again ate grape pomace, with 2 new flavors now paired with infusion of an aqueous solution (126 mmol) of NaCl (conditioning period 2) or NaH2PO4 (conditioning period 3), rather than with water. After conditioning, all lambs were offered a choice of the 3 flavors during preference tests immediately after conditioning (period 1) and every 3 wk thereafter (periods 2, 3, and 4). During period 1, when serum inorganic P levels were greatest, lambs preferred flavors paired with water > NaCl > NaH2PO4 (P < 0.05). During periods 2 and 3, as inorganic P concentrations decreased in serum, lambs preferred flavors paired with NaH2PO4 > NaCl (period 2, P = 0.10; period 3, P = 0.05). Lambs preferred flavors paired with water > NaH2PO4 in period 2 (P < 0.001), but those differences disappeared in periods 3 and 4 (P > 0.05). During period 4, lambs preferred flavors paired with NaCl > NaH2PO4 (P < 0.10). The estimate of the slope for the linear relationship between intake of flavors paired with NaH2PO4 and serum inorganic P was negative (P < 0.0001), whereas estimates of the slopes for the relationships between intake of flavors paired with NaCl or water and serum inorganic P were not different from 0. Thus, preference for P was inversely related to the concentration of serum inorganic P. Our results suggest lambs discriminated among the postingestive effects of NaH2PO4, NaCl, and water and associated those effects with specific flavors. Lambs avoided flavors paired with NaH2PO4 during periods of P replenishment, and they increased preference for those flavors during periods of P need.