impala:

-      males begin fighting with each other at ~2 months  (11)

o   dominance behaviors become evident around 18 months

o   more territorial males begin to harass juvenile males ~4.5 months, around when they are weaned from their mothers

o   at 8 months, males begin to join bachelor herds

-      bachelor males are less territorial toward each other than males in mixed herds (Bramley and Neaves 1972), express reciprocal grooming despite aggressive interactions between bachelors (Hart and Hart, 1988)

-      generally smaller than herds of females, generally a group of around 4 (Monfort-Braham, 1974)

-      in the Serengeti, immature or older males usually form smaller subgroups, while males of reproductive age are usually in mixed groups with females

-      bachelor males may rejoin the herd after being territorial on their own, though they are usually then at the bottom of the linear rank hierarchy until their physical condition is improved (Jarman MV 1979)

-      territorial males who coexist with the bachelor herds always are dominant above bachelor males (Jarman MV 1979)

Jarman, Martha J. (1974). Impala social behaviour: territory, hierarchy, mating, and the use of space.

Male impalas form small bachelor herds during both the wet and dry seasons. These bachelor herds are generally smaller than herds of females, numbering around 4 members [1]. Juvenile males begin to join bachelor herds at 8 months [2]. In the Serengeti, immature or older males will usually form smaller bachelor herds, while males of reproductive age are more often in mixed groups with females.

            Being actively territorial in the Serengeti is physically demanding for male impalas and males occupy this role for about 3 months. Males will then join a bachelor herd, though this results in them occupying a dominance status at the bottom of the linear rank hierarchy until their physical condition improves. Bachelor herds may coexist with territorial males in the same area and these individual males are always dominant above bachelor males.

            Within the herds, bachelor males are less territorial toward each other than males in mixed herds. These males maintain, on average, a distance of approximately 2.5 meters between them [3]. However, bachelor males exhibit reciprocal grooming despite occasional aggressive interactions between bachelors. seals!

-      males leave main group of females and pups and form bachelor herds far away from breeding grounds (anywhere from a mile to more)

-      most commonly killed in the seal hunt (no effect on future population)

-      live in large groups (15-20,000)

-      many live on beaches or off shore rocks (Human Impacts on Seals)

-      minimal aggression, little competition for food or mates (since it is not breeding season)

-      herds are males ranging from one year (“yearlings”) through older males

-      size of herds greatly decreases in size during breeding season Male fur seals, as a family, commonly live in bachelor herds during the non-breeding season. During the breeding season (April-September in the Northern Hemisphere, September-January in the Southern Hemisphere), the size of herds greatly diminishes. These bachelor herds are large in size, ranging from 15,000 to more than 20,000 seals living in one area.

The grounds occupied by fur seal bachelor herds are generally far away from breeding grounds, anywhere from 1 mile (1.6 km) or more. Members of the group range from seal that are one year old, called yearlings, up through older seals. There appears to be no rigid social structure during the non-breeding season and there is little competition for food or mates. The male fur seals are also mostly non-aggressive.

Fur seal bachelor herds are frequently targets of the seal hunt due to large populations being concentrated in a relatively small area. There are few regulations in regard to adult male seal hunting due to limited effects on the future population.

Mountain Zebras

-      males form bachelor herds until age 5, when they then create their own herds (of which they are the stallion)

-      male foals generally leave maternal herds after the birth of siblings or around age 2, though herd stallion does not force them out. These males then often go on to form their own bachelor herd or join an existing one

-      usually no social hierarchies

o  the older individuals exercise general control over younger members by leading the herd to feeding areas

-      when older members leave the bachelor herd to become stallions of their own herd, the next more-senior members take his social standing

o  minimal intragroup aggression, no fighting for a higher social position

-      often moves with a breeding herd (at least one member of the bachelor herd is the offspring of a mare in the breeding herd)

-      when fillies leave maternal herds (at onset of first estrus), they often join bachelor herds until they join a breeding herd or are make their own with a bachelor

Article Evaluation (separation anxiety in dogs) -appears pretty neutral -more detail could be given, as well as more hyperlinks -quite a few references seem to be missing -it is flagged with needing more references, which I agree with

Article Planning: Bachelor herd - article needs citations for what is already written - designate categories for: red deer, puku antelopes, muskoxen

Muskoxen: http://www.nrcresearchpress.com/doi/pdf/10.1139/z97-789....http://www.nrcresearchpress.com/doi/pdf/10.1139/z95-158 -smaller (on average) than mixed herds, decrease in size from late winter to summer (the now sexually mature males join a mixed herd; at the end of summer, numbers increase) -less synchronized than mixed groups by a substantial amount -dominant bulls are able to become bachelor bulls -forage significantly less than mixed herds on moist sward shrub health during the summer and rutting season; forage on different vegetation than yearlings, cows, and dominant bulls -are generally joined by subadult males that leave mixed herds due to aggression by the dominant bulls

Article Evaluation

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It's a good idea to expand the article with specific examples of bachelor herds. A section explaining the origin of the bachelor herd behaviour would be helpful (if sources exist); what groups of animals form bachelor herds? Sources for the original article are still needed and current sources need full citations. Is the definition of a bachelor herd in the first paragraph of the original article accurate? No bias is apparent in the article/draft.

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  3. ^ . doi:10.1111/j.1365-2028.1973.tb00074.x. {{cite journal}}: Cite journal requires |journal= (help); Missing or empty |title= (help)