Chimp & See Talk

Red duikers at Green Snowflake

  • Snorticus by Snorticus

    Just wondering if all the red duikers at Green Snowflake are black-fronted duikers or are some just the red duikers that don't have a dorsal stripe?

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  • AnLand by AnLand moderator

    I am not an expert here, but as far as I know, the taxonomy of the red duikers here is even in the literature uncertain. They are sometimes identified as Natal or red forest duiker (Cephalophus natalensis) - who are according to IUCN have not really their home range here. Others indicate Harvey's red duiker (Cephalophus harveyi), Peters' duiker (Cephalophus callipygus), or Weyns's duiker (Cephalophus weynsi) - if you compare known distributions for them, you see the uncertainty.

    The fur coloration varies a lot, also having individuals with black muzzles suggesting black-fronted duikers (Cephalophus nigrifrons), but it is not clear whether they indeed are. From what I read, it is not clear whether there is one or more species (or just color variations) and which one it is. So most sources I found, discuss this "uncertainty" and talk then furthermore just about "red duikers" in general.

    What is clear - and you are right with this - no black dorsal stripe for the red duikers here!

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  • Boleyn by Boleyn moderator

    @Snorticus maybe this discussion with some answers of WillemFrost may shed some light on the duiker-question but as you can see even the experts are not sure.... 😃

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  • AnLand by AnLand moderator

    As I said, there is huge uncertainty. But while Restless Star is clearly within the distribution of black-fronted duikers, Green Snowflake is not. So, we maybe should discuss whether we tag a species we are not sure about. Maybe they are black-fronted duikers, of course.

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  • Boleyn by Boleyn moderator

    Oh I thought we were in the same region as RS because of the classification map although this region is of course quite big.

    In an excerpt of Vivian J. Wilsons's book about duikers he mentions at least 5 different species of black-fronted duikers. One of their threats is dark almost black legs while the natal red duiker's legs are red as the rest of the body. This together with the darker head/throat area made me think those are the same kind of duikers as we have often seen at Restless-Star. Probably not exactly the same species but a variation of it.

    Do you think it's too risky to continue with tagging them black-fronted duikers - at least this kind with dark heads and legs?

    The pics show better what I mean:

    Green-Swnowflake
    enter image description here

    enter image description here

    Restless-Star
    enter image description here

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  • AnLand by AnLand moderator

    From your screenshots, the first one looks actually to me more like a Weyns's duiker. (But I am really no expert, sorry.)

    All I can say is that according to IUCN, Green Snowflake is not within the confirmed distribution of the black-fronted duiker (also not for the supposed subspecies of the Rwenzori red duiker (or Ruwenzori black-fronted duiker). But other variations / subspecies including hybridisation might possible.

    This is just my opinion.

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  • jwidness by jwidness moderator

    All of the red duikers here are a single species, Weyns's duikers.

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  • Boleyn by Boleyn moderator

    Do you refer on the post of @WillemFrost in the above linked thread @jwidness ?

    As far as I understood it was never 100% sure if they were Weyn's or not thus Willem suggested to tag them as black-fronted. Do we positively know that Weyn's are present at this site?
    Thanks!

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  • AnLand by AnLand moderator in response to Boleyn's comment.

    The point is that at Restless Star both species, Weyns's and black-fronted duiker, are present and confirmed, and he suggested for your example that he would rather go with black-fronted.

    At Green Snowflake, black-fronted duikers are not confirmed, but Weyns's duikers are.

    Here the taxonomic note for Weyns's duikers from IUCN that is probably responsible for the uncertainty mentioned in the literature: "Often treated as a subspecies of Peter’s Duiker Cephalophus callipygus (e.g. Kingdon 1982, East 1999, Wilson 2001) and has been previously lumped with Natal Red Duiker C. natalensis and Harvey's Red Duiker C. harveyi (Hart 2013)." (From: http://www.iucnredlist.org/details/4152/0)

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  • AnLand by AnLand moderator

    Here just a brief description for the Weyns’s duiker:

    Weyns’s duikers are medium-sized duikers in a variety of reddish to dark chestnut colors. The coloration can be more brownish at the shoulders, neck, or head. They have neither a belly, nor a dorsal stripe. The legs are darker than the body and turn to black at the hooves. The forehead is reddish-black with browner cheeks and muzzle. Kingdon mentioned that the forehead is more reinforced than in any other duiker. They have a reddish tuft of hair on the head that does not contain any black. Both sexes have horns, but a female’s horn are smaller. Juveniles are usually darker and speckled.

    Some described differences to black-fronted duikers: black-fronted duikers have a distinquishable black nose stripe that connects to the black forehead. They also have lighter (“pale”) eyebrow and reddish cheeks. The tail is black with a white tip.

    Based on José R. Castello: Bovids of the World (2016) and Jonathan Kingdon: The Kingdon Field Guide to African Mammals (2015).

    (Sorry, I can't do more.)

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  • Boleyn by Boleyn moderator

    Thanks @Anland now I'm a bit wiser concerning duikers 😃

    So we should really start to tag them weyns_duiker - at least here at GreenSnowflake. Since they seem to be the only (red) species here it should be quite easy to introduce the tag. Do you agree? The collection has already been started one year ago at RS.

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  • Snorticus by Snorticus

    Thanks all for the detailed info on these duikers and the various locations. Can we get a scientist to weigh in on how they would like them to be tagged for Green Snowflake? I have already tagged several as black-fronted duiker thinking that was correct. So I need to go back and change all those tags then?

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  • MimiA by MimiA scientist, moderator in response to Boleyn's comment.

    This makes sense to me!

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  • Boleyn by Boleyn moderator in response to Snorticus's comment.

    @Snorticus I don't think you need to go back and change them all. Just use the weyns_duiker tag from now on please. Thanks a lot!

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  • AnLand by AnLand moderator

    Do we really want to keep wrong tags? Wouldn't it be better to delete, also because others might see them and think that this is the correct tag? (We could do this from the moderators side. That would no be a problem.)

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  • Snorticus by Snorticus in response to AnLand's comment.

    I agree with Anja, I don't think we should have the wrong tags on anything if we can fix it. I will work on correcting as many of my tags to #weyns_duiker as I can find today.

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  • Orohena by Orohena

    I think that I mainly use the red_duiker tag because I was not sure. This tag we can keep and maybe add the weyns_duiker tag.
    It's the black_fronted tag that we might change.
    Am I right ?

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  • Boleyn by Boleyn moderator

    You're right @Orohena, Thank you and also @Snorticus for doing it if you like and if you find the time!

    @Anland of course we should not keep wrong tags, I just didn't want to make all our volunteers going through their recents. 😃

    I was ready to do it next week if it can wait until then, since I kind of initiated the black-fronted tag. Is that ok with you?

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  • Snorticus by Snorticus in response to Boleyn's comment.

    Hi @Boleyn, It didn't take me too long to go back through my tags since we've only been tagging Green Snowflake for a few weeks, I was happy to correct them 😃

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