Spring Diet Research Articles

Elk and Mule Deer Diets in North-Central New Mexico

Botanical composition of mule deer and elk diets in winter, spring, summer, and autumn was studied during 1998 and 1999 on woodland rangeland in north-central New Mexico using microhistological analysis of fecal samples. Our study area had no livestock grazing for 60 years but was moderately grazed by mule deer and elk. Elk and mule deer shared 3 of the top 5 key forage species when diets were pooled across seasons and years. These 3 species were oak (Quercus sp.), ponderosa pine (Pinus ponderosa Dougl.), and mullein (Verbascum thapsus L.). When data were pooled across seasons and years, overall dietary overlap between mule deer and elk was 64%. Diet overlaps of 50% or more occurred between mule deer and elk in all 4 seasons in both years of study. Throughout both years, mule deer and elk diets were dominated by browse. Mountain mahogany (Cercocarpus montanus Raf.) was the most abundant browse plant in mule deer diets; ponderosa pine was most abundant in elk diets. Both animals selected forbs, which were in low supply during the study. Scarlet globemallow (Sphaeralcea coccinea Pursh), a nutritious forb, was common in both mule deer and elk diets. Our study and others from woodland rangelands in New Mexico show high potential for forage competition between mule deer and elk. Elk are more dietarily adaptable to changing forage availability than are mule deer. Our study indicates that diets of mule deer and elk are not complementary on woodland rangelands in New Mexico. Therefore, grazing capacity is not increased by common-use grazing of the 2 animals. Both mule deer and elk herds have been increasing on our study area. Therefore, if use of common forage species is kept at moderate levels on southwestern woodland rangelands, mule deer herds can be maintained or increased when elk are present.

Digestive Organ Sizes and Enzyme Activities of Refueling Western Sandpipers (Calidris mauri): Contrasting Effects of Season and Age

We examined seasonal and age-related variation in digestive organ sizes and enzyme activities in female western sandpipers (Calidris mauri) refueling at a coastal stopover site in southern British Columbia. Adult sandpipers exhibited seasonal variation in pancreatic and intestinal enzyme activities but not in digestive system or organ sizes. Spring migrants had 22% higher total and 67% higher standardized pancreatic lipase activities but 37% lower total pancreatic amylase activity than fall migrants, which suggests that the spring diet was enriched with lipids but low in glycogen. Spring migrants also had 47% higher total intestinal maltase activity as well as 56% higher standardized maltase and 13% higher standardized aminopeptidase-N activities. Spring migrants had higher total enzymic capacity than fall migrants, due primarily to higher total lipase and maltase activities. During fall migration, the juvenile's digestive system was 10% larger than the adult's, and it was composed differently: juveniles had a 16% larger small intestine but a 27% smaller proventriculus. The juvenile's larger digestive system was associated with lower total enzymic capacity than the adult's due to 20% lower total chitinase and 23% lower total lipase activities. These results suggest that juvenile western sandpipers may process food differently from adults and/or have a lower-quality diet.

Diet Composition, Forage Selection, and Potential for Forage Competition Among Elk, Deer, and Livestock on Aspen–Sagebrush Summer Range

We evaluated elk (Cervus elaphus), mule deer (Odocoileus hemionus), cattle (Bos taurus), and domestic sheep (Ovis aries) diet composition, diet overlap, and forage selection on aspen (Populus tremuloides Michaux)–sagebrush (Artemisia spp. L.) summer range in northeastern Nevada to understand potential for forage competition to provide better information for managing these communities. Diets were determined through microhistological fecal analysis from 1998 to 2000, and forage selection was evaluated at feeding sites in aspen and sagebrush communities in 1999 and 2000. Elk spring diets were the most diverse in composition; summer elk diets were dominated by forbs (59%–78%); deer consumed mostly woody browse (64%–72%); and cattle and sheep ate mostly graminoids. Lupines (Lupinus spp. L.) constituted � 11% of elk, deer, and sheep diets in summer. Spurred lupine (Lupinus caudatus Kellogg) was the lupine typically selected in feeding sites and greatest consumption occurred in summer when total alkaloid levels were lowest. Highest diet overlap was between cattle and sheep in 1999 (68%) and lowest between deer and cattle in 2000 (3%). Summer elk and deer diets overlapped moderately (45%–59%). Diets did not differ between elk in spring with sheep, elk in summer with deer and sheep, or cattle with sheep. Cattle foraged selectively on forbs in aspen communities (68%) and on graminoids in sagebrush communities (88%), reflecting relative forage availabilities. We detected no differences among elk, cattle, and sheep for forage selection in aspen communities. Electivity indices indicated elk preferred forbs in aspen and sagebrush communities; cattle preferred graminoids in sagebrush; and foraging sheep preferred forbs in aspen. Our results suggest potential for forage competition among ungulates on aspen–sagebrush summer range is highest for forbs in aspen communities. Monitoring productivity and use of key forage species, particularly forbs in aspen communities, should complement management objectives on shared aspen–sagebrush summer range.

Elk and Mule Deer Diets in North-Central New Mexico

Botanical composition of mule deer and elk diets in winter, spring, summer, and autumn was studied during 1998 and 1999 on woodland rangeland in north-central New Mexico using microhistological analysis of fecal samples. Our study area had no livestock grazing for 60 years but was moderately grazed by mule deer and elk. Elk and mule deer shared 3 of the top 5 key forage species when diets were pooled across seasons and years. These 3 species were oak (Quercus sp.), ponderosa pine (Pinus ponderosa Dougl.), and mullein (Verbascum thapsus L.). When data were pooled across seasons and years, overall dietary overlap between mule deer and elk was 64%. Diet overlaps of 50% or more occurred between mule deer and elk in all 4 seasons in both years of study. Throughout both years, mule deer and elk diets were dominated by browse. Mountain mahogany (Cercocarpus montanus Raf.) was the most abundant browse plant in mule deer diets; ponderosa pine was most abundant in elk diets. Both animals selected forbs, which were in low supply during the study. Scarlet globemallow (Sphaeralcea coccinea Pursh), a nutritious forb, was common in both mule deer and elk diets. Our study and others from woodland rangelands in New Mexico show high potential for forage competition between mule deer and elk. Elk are more dietarily adaptable to changing forage availability than are mule deer. Our study indicates that diets of mule deer and elk are not complementary on woodland rangelands in New Mexico. Therefore, grazing capacity is not increased by common-use grazing of the 2 animals. Both mule deer and elk herds have been increasing on our study area. Therefore, if use of common forage species is kept at moderate levels on southwestern woodland rangelands, mule deer herds can be maintained or increased when elk are present.

Diet Composition, Forage Selection, and Potential for Forage Competition Among Elk, Deer, and Livestock on Aspen-Sagebrush Summer Range

We evaluated elk (Cervus elaphus), mule deer (Odocoileus hemionus), cattle (Bos taurus), and domestic sheep (Ovis aries) diet composition, diet overlap, and forage selection on aspen (Populus tremuloides Michaux)-sagebrush (Artemisia spp. L.) summer range in northeastern Nevada to understand potential for forage competition to provide better information for managing these communities. Diets were determined through microhistological fecal analysis from 1998 to 2000, and forage selection was evaluated at feeding sites in aspen and sagebrush communities in 1999 and 2000. Elk spring diets were the most diverse in composition; summer elk diets were dominated by forbs (59%-78%); deer consumed mostly woody browse (64%-72%); and cattle and sheep ate mostly graminoids. Lupines (Lupinus spp. L.) constituted > 11% of elk, deer, and sheep diets in summer. Spurred lupine (Lupinus caudatus Kellogg) was the lupine typically selected in feeding sites and greatest consumption occurred in summer when total alkaloid levels were lowest. Highest diet overlap was between cattle and sheep in 1999 (68%) and lowest between deer and cattle in 2000 (3%). Summer elk and deer diets overlapped moderately (45%-59%). Diets did not differ between elk in spring with sheep, elk in summer with deer and sheep, or cattle with sheep. Cattle foraged selectively on forbs in aspen communities (68%) and on graminoids in sagebrush communities (88%), reflecting relative forage availabilities. We detected no differences among elk, cattle, and sheep for forage selection in aspen communities. Electivity indices indicated elk preferred forbs in aspen and sagebrush communities; cattle preferred graminoids in sagebrush; and foraging sheep preferred forbs in aspen. Our results suggest potential for forage competition among ungulates on aspen-sagebrush summer range is highest for forbs in aspen communities. Monitoring productivity and use of key forage species, particularly forbs in aspen communities, should complement management objectives on shared aspen-sagebrush summer range.

How to write for the public

The spring diet season is here and people are wondering what to eat. The first case of mad cow disease (bovine spongiform encephalopathy) has been identified in a cow in Washington State, and the meat from the cow presumably has entered the meat supply, especially on the West Coast. On the East Coast, a recent study has just concluded that consuming farm-raised salmon poses greater health risks than eating salmon caught in the wild, because the farm-raised varieties have been fed ground fish products contaminated with potentially carcinogenic PCBs ( 1 Hites R.A. Foran J.A. Carpenter D.O. Hamilton M.C. Knuth B.A. Schwager S.J. Global assessment of organic contaminants in farmed salmon. Science. 2004; 303 (as reported in The New York Times, Jan. 9, 2004, p.10.): 226-229 Crossref PubMed Scopus (701) Google Scholar ). The Food and Drug Administration, in its first such act against an herbal supplement, has banned sales of ephedra, and the airwaves are flooded with weight loss ads for diet pills and ephedra-free “natural” compounds.

Seasonal Changes and Selectivity in the Diet of Brown Trout in the River Nera (Central Italy)

ABSTRACT The stomach contents of brown trout from the middle region of the Nera River, Central Italy, were compared with the composition of the macroinvertebrate community of the same river stretch. The epibenthic fauna, identified mostly at the species level, was composed mainly of Ephemeroptera (Serratella ignita, Baetis spp., Rhithrogena semicolorata), Plecoptera (Dinocras cephalotes), Trichoptera (Hydropsyche sp., Micrasema spp.) and Diptera. We found that the dietary composition of brown trout was not simply proportional to the environmental density of the prey. Ephemeroptera dominated the spring and summer diets; Trichoptera prevailed in winter. The electivity index showed a negative selection towards Baetis spp. and chironomids and positive values of selection for Trichoptera. Dimensions, mobility, degree of exposure, and visibility of prey, were important factors in shaping brown trout's diet. Nevertheless species of the genera Micrasema and Lepidostoma, despite their reduced dimensions and scarce mobility, became in winter the favorite prey. This was probably due to the wintering habitat choice of the trout, under the river banks and hidden in the vegetation.

NUTRITIONAL VALUE OF YELLOW-POPLAR FLOWERS TO DEER IN THE SOUTHERN APPALACHIANS

Yellow-poplar (Liriodendron tulipifera) flowers have been re- ported to be an important component of the spring diets of white-tailed deer (Odocoileus virginianus) in the southern Appalachians. We quantified the nutri- tional contribution of yellow-poplar flowers by comparing flower nutrient con- tent to published nutrient requirements for deer. Yellow-poplar flowers ex- ceeded the calcium, phosphorus, crude protein, and digestible energy require- ments (P < 0.001) for productive processes. However, sodium requirements for antler growth and digestible energy requirements for peak lactation for twin fawns were not met by yellow-poplar flowers. Similar to oak (Quercus spp.) mast in the fall months, yellow-poplar flowers are an important seasonal source of energy for deer.

Field Vole Microtus agrestis abundance and Hen Harrier Circus cyaneus diet and breeding in Scotland

In many parts of the global range, voles form an important part of the diet of Hen Harriers Circus cyaneus, and breeding numbers are correlated with the abundance of these small mammals. In Scotland, however, little information is available on harrier diet in the spring and our understanding of causes of variation in harrier breeding density is complicated by human interference. In this paper we explore the relationship between Field Vole Microtus agrestis abundance and harrier spring diet, density and productivity in southern Scotland. Over three years, voles occurred on average in 67% of pellets, and 79% in years of high and intermediate vole abundance. From 1992, the number of breeding harriers increased following protection from illegal persecution. After accounting for this trend, harrier numbers correlated strongly with vole abundance. Harrier clutch size was also correlated with vole abundance. Although fledging success tended to be greater in years of vole increase than in years of vole decline, fledging success was not significantly correlated with the relative abundance of voles, or with the abundance of Meadow Pipits or Red Grouse chicks.

Feeding Activity and Seasonal Changes in Prey Composition of urban Peregrine FalconsFalco peregrinus

Despite the increasing populations of Peregrine Falcons in European cities, detailed quantitative studies of their diet composition and feeding activity in urban environments are rare. The results from observations in Warsaw have added to the knowledge of the feeding ecology of urban raptors. In 2000 and 2001 the same pair of Peregrines bred successfully in nest boxes situated on two different buildings in the city centre, rearing three and four chicks in the respective years. During the breeding seasons from hatching to fledging, the nests were monitored with a video camera. Only diurnal observations were used in the detailed analysis of feeding activity — 428 h in 2000 (33 days) and 384 h (24 days) in 2001. Two peaks of parental activity were noted: in the morning and in the afternoon. Additional data collected in 2000 showed that the falcons also fed their young at night. In 1998–2001 486 prey remains were collected on the buildings occupied by the Peregrines. In Warsaw these falcons preyed most often on Feral Pigeons (32%), and also on various thrush species (23.5%), Skylarks (8%) and Corncrakes (5.6%). Seasonal variations in prey composition were identified. During the spring and autumn migrations, the proportion of pigeons in the falcons' diet was 10–19%, while in summer and winter it was over 40%. The trend was reversed with regard to migrant species, which were prevalent in the diet in spring and autumn, but less numerous in summer and winter.

Biology of the Southern Scrub-robin (Drymodes brunneopygia) at Peron Peninsula, Western Australia

The ecology of the Southern Scrub-robin was examined at a 55-ha study site on the eastern side of Peron Peninsula, Western Australia. The scrub-robin was a sedentary, ground-dwelling species occurring in pairs, and sometimes alone. Pairs maintained permanent, all-purpose territories throughout the year, and males regularly defended the boundaries of their territories by song and by chasing intruders. Territory sizes ranged from 2.8 to 7.1 ha, with a mean of 4.0 ha. The female alone was observed building the nest and incubating the one egg, but both adults were seen feeding young. The incubation period was estimated at 16 days and the nestling period at 9–12 days. Scrub-robins primarily gleaned prey from leaf litter and sand. Analysis of scats showed that ants comprised a major component of the diet in both spring and summer. Other dietary items in spring included beetles, lepidopteran larvae, termites, hemipterans, spiders and fruit of Enchylaena tomentosa. In summer there was a higher proportion of termites in scats than in spring. The ant fauna within scrub-robin scats was dominated by a species of Iridomyrmex and a species of Crematogaster, both 2–3 mm in length. The Crematogaster species was selected more frequently than it occurred in litter samples, while the Iridomyrmex species was eaten in a lower proportion than sampled in the litter. The scrub-robin's use of litter substrates for feeding and nesting, and its clutch size of one and potentially low reproductive rate, suggest that it may be vulnerable to changes in the quantity and quality of the litter layer in the Western Australian wheatbelt.

Nutritional Quality of Shinnery Oak Buds and Catkins in Response to Burning or Herbivory

Nutritional Quality of Shinnery Oak Buds and Catkins in Response to Burning or Herbivory

Interannual variation in the summer diets of harbour seals Phocavitulina at Mousa, Shetland (UK)

The main prey species in the summer (July–September) diets of harbour seals (Phoca vitulina) on the Island of Mousa (Shetland, UK), 1994–1997, were whiting (Merlangius merlangus), herring (Clupea harengus), sandeel (Ammodytidae) and garfish (Belone belone). Norway pout (Trisopterus esmarkii) was numerically important but comprised no more than 11% of prey weight in any year. There were marked between-year fluctuations in the relative importance of these prey, with whiting comprising 16–34% (by weight) of the diet, herring 12–28%, sandeels 7–18% and garfish 7–22%. Additional data on spring (April–June) diet were available for 1995–1997: sandeels were the most important prey (% weight) in all three years (51–60% of the diet), while herring (8–48%) and gadids (2–22%) varied in importance. The average size of fish eaten was larger than that reported in comparable studies from other areas. Harbour seals appear to have selected larger sandeels, whiting and Norway pout than the average size available in the area, as indicated by survey trawls, although between-year changes in the size of Norway pout in the diet did to some extent reflect availability. Interannual variation in the importance of Norway pout in the diet appeared to track trends in abundance, although the short time series precluded detection of a statistically significant correlation. Thus, some of our results are consistent with harbour seals feeding opportunistically while others point to selectivity, particularly for prey size. Estimated consumption of fish by the 500 harbour seals on Mousa during summer ranged from 152–195 tonnes.

Spring diet of the endemic ring-tailed cat (Bassariscus astutus insulicola) population on an island in the Gulf of California, Mexico

The spring diet of an endemic ring-tailed cat (Bassariscus astutus insulicola) population of Isla San José, Gulf of California, Mexico, is presented based on the analysis of 104 faeces. The ring-tailed cat is an opportunistic species, concentrating on the predation of mainly small prey, and has a richness of prey of 36 animal taxa and 12 plant species. The most important prey were found to be mainly Orthoptera, Tenebrionida, and Scorpionoidea, Chaetodipus spinatus and Neotoma lepida. Chilomeniscus cinctus, Cnemidophorus, and Sceloporus were the most important reptile species. Among the plant species, of particular importance were the fruits of Lycium,Solanum , Phaulothamnus, and ironwood leaves. The spring diet of the ring-tailed cats of Isla San José differs from the diet of all other mainland populations, in that the proportion of reptiles (50% of occurrence) and invertebrates (91%) were found to be of the highest ever reported, even when compared with other seasons.

Diet of tawny owls (Strix aluco) in relation to field vole (Microtus agrestis) abundance in a conifer forest in northern England

AbstractThe diet of tawny owls Strix aluco was determined from pellets and prey items in owl nests in Kielder Forest, a planted spruce forest in northern England. Field voles Microtus agrestis were their most important food, and formed the highest proportion of tawny owl diet in winter and early spring. Common shrews Sorex araneus, common frogs Rana temporaria and birds were taken more frequently in late spring and summer. Clear cuts, areas from which timber had been felled at the end of the rotation, provided the main field vole habitat in the forest and remained suitable for voles for 10–15 years after re‐planting. Field vole abundance was measured three times a year on numerous clear cuts throughout the study area using a vole sign index based on fresh grass clippings in runways. Tawny owls responded functionally to the 3 to 4‐year cycles of field vole abundance. In years when voles were scarce, adult owls took more common shrews and common frogs, as determined from pellet analysis. In contrast, more bird prey was fed to nestlings when field voles were scarce, as determined from prey items in nests. The proportions of the main prey in nests changed over a 19‐year period. More bank voles Clethrionomys glareolus and wood mice Apodemus sylvaticus occurred in every year after 1992 than in any year before this. Numbers of wood mice in owl nests increased significantly throughout the study period, whereas bank vole numbers exhibited non‐cyclic, multi‐annual fluctuations that were unrelated to field vole cycles. It is argued that fluctuations in rodent prey reflected changes in rodent guilds in the study area; reasons for this are discussed. This is the first study of tawny owl diet in spruce forests in Britain and highlights the value of such large‐scale dynamic habitats for rodent populations and their predators.

Changes in the botanical composition and nutritive characteristics of pasture, and nutrient selection by dairy cows grazing rainfed pastures in western Victoria

Changes in pasture metabolisable energy (ME), crude protein (CP), neutral detergent fibre (NDF), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), sodium (Na) and chlorine (Cl) were measured at each grazing, in 4 paddocks on 2 farms (farm A and farm B) in western Victoria from May 1995 to March 1997. Selection differentials were calculated from quality parameters using measures of pre- and post-grazing masses. Changes in botanical composition and pasture allowance were also measured. The nutritive characteristics of pasture on both farms followed similar trends. Metabolisable energy and CP were highest in winter and early spring with values of over 11 MJ/kg DM and 250 g/kg DM respectively. The lowest concentrations of ME and CP in pasture on farm A (9.4 MJ/kg DM; 128 g/kg DM) were observed in April and February respectively. On farm B the corresponding lowest values (8.4 MJ/kg DM; 100 g/kg DM) were in March. In contrast, NDF values on farm A were lowest in June (466 g/kg DM) and on farm B (436 g/kg DM) in May, with highest values in February (648 g/kg DM) and March (692 g/kg DM) respectively. Concentrations of P, K, S and Cl in pasture followed a similar pattern to that of ME with highest values in winter and lowest in summer, while changes in Ca concentrations related more closely to changes in NDF. The concentrations of Mg and Na were highest in autumn and spring, respectively, with lowest values in late spring and summer. Selection differentials indicated that the ME of pasture consumed was 4–22% higher than the pasture on offer. For CP the range of selection differentials was always greater than 1, but varied widely (1.08–1.83). The selection differentials for NDF were always negative, with an average value of 0.84. Selection differentials for minerals varied little over the year, with values generally indicating a positive selection differential (P 1.12, 1.15; Ca 1.16, 1.16; Mg 1.15, 1.18; K 1.23, 1.27; Na 1.05, 1.07; Cl 1.16, 1.14; S 1.27, 1.28) for farms A and B. Pasture allowances ranged from 10–60 kg DM/cow.day and there was no relationship between selection differentials for all nutritive characteristics and pasture allowance. The results obtained in this study indicated that although the ME of pasture consumed throughout the year should be adequate to meet production of 30 L/cow.day in early lactation with minimal liveweight loss, it was associated with high levels of CP and potentially low concentrations of NDF in relation to cow requirements. Results therefore indicate a possible need for supplementing pasture diets in winter and spring to balance the diet for CP and NDF. In addition, it is likely that both Ca and Mg intake from pasture may be limiting in early lactation and therefore additional supplements of both minerals may be required during this period.

Effects of Spring Feeding on Body Condition of Captive-Reared Ring-Necked Pheasants in Great Britain

In Great Britain, the captive rearing and release of ring-necked pheasants (Phasianus colchicus) during summer to supplement wild stocks for shooting is widespread, but breeding success of surviving females the following spring is poor. We hypothesized that reduced body condition as caused by low availability of natural food during spring and cessation of supplemental feeding in late winter may affect subsequent breeding success. On an estate in southern England, we provided wheat grain on 3 l-km 2 plots from March to June, while pheasants on 3 other l-km 2 plots foraged solely on natural foods. We switched treatments during the second year. We collected hen pheasants from each plot during February and April. Fat reserves of hen pheasants collected in April from food-supplemented plots were maintained at their February levels (76.9 ± 8.0 g; x ± SE), but fat reserves of birds collected from unsupplemented plots were reduced by >50% of their Febmary levels (34.7 ± 6.9 g; P = 0.01). Body mass, muscle sizes, ceca, and small intestine length were more affected by date than supplemental feeding. We suggest that low food availability and poor spring diet as a result of modern agriculture may affect hen body condition and productivity of pheasants in Great Britain.

Spatial and Temporal Patterns in Arctic Fox Diets at a Large Goose Colony

We studied diets of arctic foxes ( Alopex lagopus ) associated with a large nesting colony of lesser snow and Ross's geese in the central Canadian Arctic. From 15 May to 5 August 1994 and from 18 May to 7 August 1995, we examined arctic fox diets using frequency of occurrence of prey remains in faeces. Most scats (n=791 of 817, or 97%) were collected from den sites. Scats from foxes with dens inside the goose colony contained eggs more frequently than those of foxes that depended more on small mammals outside the colony. Foxes were opportunistic in their feeding habits, as prey use was linked to the nesting cycle of geese, coinciding to periods of egg, goose, and gosling abundance. However, diets in spring, i.e., before geese arrive, reflected the importance to arctic foxes of caching geese and eggs from the previous summer at Karrak Lake. We suggest that large increases in nesting populations of lesser snow and Ross's geese may have beneficial implications for arctic fox populations over a large area.

The Diet of Goats, Red Deer and South American Camelids Feeding on Three Contrasting Scottish Upland Vegetation Communities

1. With changes in the agricultural policy for rural areas in the UK there is increased interest in the development of management protocols for indigenous and sown swards in upland Scotland based on grazing by ruminant species other than sheep and cattle, e.g. goats, red deer and South American camelids. 2. Here we describe the diet composition over two seasons of goats, red deer and South American camelids (guanacos) grazing three vegetation types typical of upland ecosystems in the UK: a sown sward (Lolium perenne-dominated), an indigenous grassland (Nardus stricta-dominated) and a dwarf shrub community (Calluna vulgaris-dominated). 3. On each vegetation type, all three animal species were selective feeders. The composition of the goats' diet was more variable than that of the red deer and guanacos. All three species were more selective when grazing the indigenous communities than when grazing the sown sward. 4. On the Lolium sward, the guanacos avoided clover and other dicotyledonous plants, whilst the goats and red deer consumed green leaf from all plant categories found at or near the sward surface. 5. On the Nardus community, all three species avoided the dominant tussock-grass and selected green lamina of broad-leaved grasses from the species-rich inter-tussock areas. Between-species differences in minor components included an increased contribution of non-grass monocotyledonous plants to the goats' diet in spring, and a higher proportion of grass flowerstem and grass seed/flowerhead in the guanacos' diet in summer. 6. The diets of the three species of animal on the Calluna community were broadly similar. All generally avoided C. vulgaris and strongly selected graminoid species. Consumption of grass was greater in spring than summer. 7. Species differences in diet composition, particularly on indigenous swards dominated by N. stricta and C. vulgaris, might facilitate vegetation management and improve animal output using multispecies grazing systems.

Threatened fishes of the world: Galaxiella munda McDowall, 1978 (Galaxiidae)

Common name: Western mud minnow. Conservation status: Restricted (Australian Society for Fish Biology’s list of Australian threatened fishes). Identification: D 6–8, A 9–12, P 9–12, V 5–7, C 13–15, vertebrae 38–43, myomeres 41–43. Maximum size 58 mm TL. A small freshwater fish with a scaleless, elongate slender body and long straight gut reaching about 65–70% of the body length. Dorsal fin is posteriorly placed and originates posterior to the vertical that passes through the fifth anal ray, no adipose fin is present. Between June and October adults of this species are characterised by their coloration which consists of two olive-brown longitudinal bands separated by an orange stripe and a silver belly. The colored lateral stripe gradually dissipates to become a thin silver-white line after October and by January most fish are a fairly uniform light olive-brown in color. Drawing by Howard Gill. Distribution: G. munda is restricted to a small area in the south-western corner of Australia that extends from Albany in the east to Margaret River in the west, with an isolated population 350 km north at Gingin (McDowall & Frankenberg 1981, Allen 1989, Gill & Neira 1994). It is likely that the discontinuity in the distribution of this species represents the loss of suitable habitat caused by widespread urban and rural development in this region. Abundance: This species is rare throughout most of its distribution, but is occasionally locally abundant. Habitat and ecology: G. munda is typically found in small streams or shallow pools connected to streams (Pen et al. 1991). Water temperature ranges from 11.0–23.0° C. Terrestrial fauna (dipterans) and dipteran larvae and pupae are the main component of the diet in winter, spring and summer, while cladocerans and copepods form the most important component in autumn. The life cycle of G. munda typically lasts for just over one year (Pen et al. 1991). Reproduction: At the end of their first year of life females and males reach total lengths of 47 and 43 mm, respectively, at which time individuals attain sexual maturity and develop a breeding livery of two olivebrown longitudinal bands separated by an orange stripe. The mean GSIs of females rise from less than 2.0 in February to a maximum of 15.0 in August before falling sharply to less than 1.5 in November, the mean GSIs of males follow a similar trend. This species is a multiple spawner and breeds between July and October with a peak in activity in late August, a period when water temperatures and daylength have begun to rise. Threats: Habitat alteration and the introduction of exotic species pose the main threats to G. munda and also the three other species endemic to this region. Habitat alteration is likely to occur through, the construction of dams, groundwater extraction and also agricultural and forestry practices in the uppermost catchment (causing alterations to inflow, salinisation, siltation and eutrophication). It should be noted that the introduction of exotic fish species (Gambusia holbrooki, Perca fluviatilis, Onchorhynchus mykiss and Salmo trutta) and those species translocated from eastern Australia (Macquaria ambigua and Bidyanus bidyanus) has already occurred in many of the major catchments in the region. The combined effects of habitat alteration and introductions may explain the apparent loss of G. munda from the headwaters of Lefroy Brook. Thus, whereas Pen et al. (1991) reported viable populations of this species in these waters, an ongoing study has failed to record any G. munda in these streams (Morgan unpublished data). It is therefore pertinent that during several recent dry years the reservoir immediately above a major dam was the only upstream section of Lefroy Brook to retain water during summer and autumn. Furthermore, during these dry years, the piscivorous P. fluviatilis was introduced to the reservoir and is now well established in this reservoir and the headwater streams. Conservation recommendations: The most important conservation is the preservation of ‘natural’ flow regimes and suitable habitat in the small streams of south-western Australia, to ensure this buffer zones must be maintained in areas used for both farming and forestry, and further introductions of non-endemic species should be prohibited. Remarks: G. munda is one of only eight species of freshwater fish that are endemic to south-western Australia.