Rhino Numbers and Census
- Richprins
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Re: Rhino Numbers and Census
I think this should be better, as it is private money so MUST be spent properly with results!
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Re: Rhino Numbers and Census
Vol. 61 (2020): Pachyderm
PUBLISHED: 2020-10-08
Read the full article here:
https://pachydermjournal.org/index.php/ ... view/8/320
PUBLISHED: 2020-10-08
Read the full article here:
https://pachydermjournal.org/index.php/ ... view/8/320
Evaluating uncertainty in estimates of large rhinoceros populations
Sam M Ferreira1* and Danie Pienaar11Scientific Services, SANParks, Skukuza, 1350, South Africa*corresponding author: sam.ferreira@sanparks.org
Abstract
Estimates of the numbers of living rhinoceroses inform management interventions. Several techniques assist authorities in obtaining estimates. For large populations, authorities use sample-based methods. Estimates for the number of rhinos living in Kruger National Park (Kruger) make use of sample-based block surveys. Critics of this approach allege that the authorities place sample blocks mostly in areas with high rhino numbers and that this, together with correction for various biases, inflates estimates. The critics also claim that the percentage confidence intervals (PCIs) associated with estimates are too large and propose total area counts as an alternative. We assess these criticisms by comparing the results of a sample-based survey with those of a near concurrent total count. We found that sample surveys appeared to focus on areas with higher rhino densities, but rhino movements in and out of the survey area confounded results. Moreover, total counts do not produce reliable estimates when surveyors fail to account for biases inherent to all sampling procedures. Bias corrections used by sample surveys most likely underestimate the number of rhinos that surveyors miss, contrary to the allegations of critics that sample-based techniques inflate population estimates. Even so, estimates that transparently report uncertainties detected a significant decline in white rhinos from 8,968 (95% CI: 8,394–9,564) in 2013 to 4,116 (95% CI: 2,994–5,726) in 2018. The trends in the black rhino population also indicate a decline from 627 (95% CI: 588–666) in 2009 to 291 (95% CI: 151–441) in 2018. Conducting block-based sample surveys for large populations that correct for biases provides useful information for decision makers. Given that South Africa, specifically Kruger makes substantial contributions to continental rhino numbers, reporting to international bodies such as CITES should transparently include the uncertainties associated with population estimates.
- Richprins
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Re: Rhino Numbers and Census
What a silly story.
We found that sample surveys appeared to focus on areas with higher rhino densities,
That is what we have been saying!
So the rhino population more than half dead in 5 years.
We found that sample surveys appeared to focus on areas with higher rhino densities,
That is what we have been saying!
So the rhino population more than half dead in 5 years.
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- Alf
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Re: Rhino Numbers and Census
They work on Africa time
And then after how many years they realize what we were saying
And then after how many years they realize what we were saying
Next trip to the bush??
Let me think......................
Let me think......................
- Richprins
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Re: Rhino Numbers and Census
Article in Beeld on 21 October:
Basically Kruger confirms the drastic drop in rhino from 2013-18, and especially 2017-18, and attributes it to poaching.
Basically Kruger confirms the drastic drop in rhino from 2013-18, and especially 2017-18, and attributes it to poaching.
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- Lisbeth
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Re: Rhino Numbers and Census
What else could it be?
"Education is the most powerful weapon which you can use to change the world." Nelson Mandela
The desire for equality must never exceed the demands of knowledge
The desire for equality must never exceed the demands of knowledge
- Richprins
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Re: Rhino Numbers and Census
From 2019/20 SANParks report, page 97:
The 2019 rhino estimates
for Kruger National Park stand at 268 black (95% CI: 191-342) and 3,549 white
(95% CI: 3 152-3 949) rhinos, with births equalling combined natural and poaching
deaths for the first time in five years
https://pmg.org.za/page/Annual%20Report ... 20-%202020
The 2019 rhino estimates
for Kruger National Park stand at 268 black (95% CI: 191-342) and 3,549 white
(95% CI: 3 152-3 949) rhinos, with births equalling combined natural and poaching
deaths for the first time in five years
https://pmg.org.za/page/Annual%20Report ... 20-%202020
Last edited by Richprins on Wed Jan 27, 2021 6:20 pm, edited 1 time in total.
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- Richprins
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Re: Rhino Numbers and Census
Down from 4116 and up from 219 respectively in 2018.
How can this equal births?
How can this equal births?
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- Lisbeth
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Re: Rhino Numbers and Census
Some people are not good when it comes to numbers
"Education is the most powerful weapon which you can use to change the world." Nelson Mandela
The desire for equality must never exceed the demands of knowledge
The desire for equality must never exceed the demands of knowledge