Swift again: was Re: [NatureNS] 50th Anniversary of Silent Spring

From: Christopher Majka <c.majka@ns.sympatico.ca>
To: naturens@chebucto.ns.ca
Date: Tue, 24 Apr 2012 18:51:37 -0300
References: <010601cd1dbc$d2f45ee0$78dd1ca0$@ns.sympatico.ca> <5C30DF2C51F04256B0D20BA95665515B@D58WQPH1> <CADF8qtY+gVjJCwQ=Zrn6TMsXcUFZ0U9C0qyhvcXNiNabiPrEZA@mail.gmail.com> <4FF17CF91C664C76856670D86931813D@D58WQPH1> <B121D6BF-4491-44E0-9FE0-DA45D80CE7CB@ns.sympatico.ca> <20120423193316.17011dczzguxzzr4@wm4.dal.ca> <BE708AB1-6E6B-41E8-9088-695B8F99115E@ns.sympatico.ca> <622FEB34802E4D8AAFB28E7E44F2787B@D58WQPH1>
Precedence: bulk
Return-Path: <naturens-mml-owner@chebucto.ns.ca>
Original-Recipient: rfc822;"| (cd /csuite/info/Environment/FNSN/MList; /csuite/lib/arch2html)"

next message in archive
no next message in thread
previous message in archive
previous message in thread
Index of Subjects

circa 1945) indicates that levels of DDE were at almost 0 

--Apple-Mail-79-514812118
Content-Type: text/plain;
	charset=US-ASCII;
	format=flowed;
	delsp=yes
Content-Transfer-Encoding: 7bit

Hi Dave,

On 24-Apr-12, at 5:55 PM, David & Alison Webster wrote:

> Hi Chris & All,                    Apr 24, 2012
>     I had to sit this one until now. busy with income tax.
>
>     We could get bogged down in small points but, quite apart from  
> muddy presentation, the big picture bothers me more. The statistics  
> in the paper deal with measurement error and associations between  
> variates but can not define experimental error because they had only  
> one roost.

It is only one study, but science begins from single studies and then  
adds more which either confirm or refute the initial findings. The  
circumstances which permitted this study (i.e., a lengthy historical  
guano deposit) may not be all that common.

>     From this case study of one roost it is therefore entirely  
> unsound to apply the conclusions to the entire Swift population.  
> Measuring one hen egg a million times, to obtain absolute precision,  
> does not provide any insight into the dimensions of eggs in general  
> or even of hen eggs in general.

True, but the author's of this study were not measuring the same data  
a million times.

>     A quote from DISCUSSION says it all; "Their (Swift) population  
> declines are probably a product of the general decrease in relative  
> abundance of Coleoptera from the early 1970 to 1992 (Fig. 2c)  
> [sic"]: 2b intended.

No, this is not what they say. You have selectively edited the  
sentence to alter its meaning. The full sentence reads:

"Their population declines are probably a product of the general  
decrease in relative abundance of Coleoptera from the early 1970 to  
1992 (figure 2c), and multiple environmental stressors, ranging from  
climate change to habitat loss. [49, 50]" (my emphasis) which makes  
clear that the change in diet is probably only one of several factors  
that have contributed to their much decreased abundance - a 96%  
decline in abundance since 1968.

Furthermore the two references cited here, Cink & Collins (2002) and  
Parmesan (2006), provide additional evidence to support this contention.

>     To swallow the above (no pun intended) you have to accept that--
> 1) Beetles and true bugs constitute the Swift's diet almost entirely,

The data presented in Figures 2(a) & 2(b) shows that this appears to  
be so.

> 2) A questionably significant decrease in relative abundance of  
> Beetle debris from 0.6 to 0.4 contributed to a 90% decline in Swift  
> population and

No, incorrect. As the full sentence above makes clear, dietary change  
is only one of several factors contributing to the decline.

> 3) Essentially the same decrease in Beetle relative abundance would  
> be found in roosts throughout the range of Chimney Swifts.

The author's make no such claim in the paper, nor do I believe they  
would argue this, nor is this a necessary assumption to any of their  
conclusions. If this study were to be replicated elsewhere, relative  
Coleoptera abundance might be similar or different, and population  
declines in swifts at that site might, again be similar or different.  
Such a study would need to be undertaken to determine both of these.

Truncating the second sentence of the fourth paragraph of the  
discussion completely alters its meaning and leads you to draw  
incorrect assumptions about what the study is predicated on and implies.

Cheers!

Chris


Christopher Majka  <c.majka@ns.sympatico.ca> | Halifax, Nova Scotia,  
Canada

* Research Associate: Nova Scotia Museum | http://museum.gov.ns.ca/mnh/research-asfr.htm
* Review Editor: The Coleopterists Bulletin | http://www.coleopsoc.org/
* Subject Editor: ZooKeys | http://pensoftonline.net/zookeys/index.php/journal/index
* Review Editor: Zootaxa | http://www.mapress.com/zootaxa/taxa/Coleoptera.html
* Associate Editor: Journal of the Acadian Entomological Society | http://www.acadianes.org/journal.html
* Editor: Atlantic Canada Coleoptera | http://www.chebucto.ns.ca/Environment/NHR/PDF/index.html
* Editor: Bugguide, Coleoptera http://bugguide.net

Whenever I hear of the capture of rare beetles, I feel like an old war- 
horse at the sound of a trumpet. - Charles Darwin


--Apple-Mail-79-514812118
Content-Type: text/html;
	charset=US-ASCII
Content-Transfer-Encoding: quoted-printable

<html><body style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; =
-webkit-line-break: after-white-space; ">Hi Dave,<div><br><div><div>On =
24-Apr-12, at 5:55 PM, David &amp; Alison Webster wrote:</div><br =
class=3D"Apple-interchange-newline"><blockquote type=3D"cite"><span =
class=3D"Apple-style-span" style=3D"border-collapse: separate; color: =
rgb(0, 0, 0); font-family: 'Times New Roman'; font-style: normal; =
font-variant: normal; font-weight: normal; letter-spacing: normal; =
line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: =
0px; text-transform: none; white-space: normal; widows: 2; word-spacing: =
0px; -webkit-border-horizontal-spacing: 0px; =
-webkit-border-vertical-spacing: 0px; =
-webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
bgcolor=3D"#ffffff" style=3D"word-wrap: break-word; -webkit-nbsp-mode: =
space; -webkit-line-break: after-white-space; "><div><font size=3D"2">Hi =
Chris &amp; All,&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; =
&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; Apr 24, =
2012</font></div><div><font size=3D"2">&nbsp;&nbsp;&nbsp; I had to sit =
this one until now. busy with income tax.</font></div><div><font =
size=3D"2"></font>&nbsp;</div><div><font size=3D"2">&nbsp;&nbsp;&nbsp; =
We could get bogged down in small points but, quite&nbsp;apart from =
muddy presentation,&nbsp;the big picture bothers me more. The statistics =
in the paper deal with measurement error and associations between =
variates but can not define experimental error because they had only one =
roost.</font></div></div></span></blockquote><div><br></div><div>It is =
only one study, but science begins from single studies and then adds =
more which either confirm or refute the initial findings. The =
circumstances which permitted this study (i.e., a lengthy historical =
guano deposit) may not be all that common.</div><br><blockquote =
type=3D"cite"><span class=3D"Apple-style-span" style=3D"border-collapse: =
separate; color: rgb(0, 0, 0); font-family: 'Times New Roman'; =
font-style: normal; font-variant: normal; font-weight: normal; =
letter-spacing: normal; line-height: normal; orphans: 2; text-align: =
-webkit-auto; text-indent: 0px; text-transform: none; white-space: =
normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: =
0px; -webkit-border-vertical-spacing: 0px; =
-webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
bgcolor=3D"#ffffff" style=3D"word-wrap: break-word; -webkit-nbsp-mode: =
space; -webkit-line-break: after-white-space; "><div><font =
size=3D"2">&nbsp;&nbsp;&nbsp; =46rom this case study of one roost it is =
therefore entirely unsound to apply the conclusions to the entire Swift =
population. Measuring one hen egg a million times, to obtain absolute =
precision, does not provide any insight into&nbsp;the dimensions of eggs =
in general or even of hen eggs in =
general.</font></div></div></span></blockquote><div><br></div><div>True, =
but the author's of this study were not measuring the same data a =
million times.</div><br><blockquote type=3D"cite"><span =
class=3D"Apple-style-span" style=3D"border-collapse: separate; color: =
rgb(0, 0, 0); font-family: 'Times New Roman'; font-style: normal; =
font-variant: normal; font-weight: normal; letter-spacing: normal; =
line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: =
0px; text-transform: none; white-space: normal; widows: 2; word-spacing: =
0px; -webkit-border-horizontal-spacing: 0px; =
-webkit-border-vertical-spacing: 0px; =
-webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
bgcolor=3D"#ffffff" style=3D"word-wrap: break-word; -webkit-nbsp-mode: =
space; -webkit-line-break: after-white-space; "><div><font =
size=3D"2">&nbsp;&nbsp;&nbsp; A quote from DISCUSSION says it all; =
"Their (Swift) population declines are probably a product of the general =
decrease in relative abundance of Coleoptera from the early 1970 to 1992 =
(Fig. 2c) [sic"]: 2b =
intended.</font></div></div></span></blockquote><div><br></div><div>No, =
this is <b>not</b> what they say. You have selectively edited the =
sentence to alter its meaning. The full sentence =
reads:</div><div><br></div><div><div bgcolor=3D"#ffffff"><div>"Their =
population declines are probably a product of the general decrease in =
relative abundance of Coleoptera from the early 1970 to 1992 (figure =
2c),<i> and multiple environmental stressors, ranging from climate =
change to habitat loss. </i>[49, 50]" (my emphasis) which makes clear =
that the change in diet is probably only one of several factors that =
have contributed to their much decreased abundance - a 96% decline in =
abundance since 1968.</div><div><br></div><div>Furthermore the two =
references cited here, Cink &amp; Collins (2002) and Parmesan (2006), =
provide additional evidence to support this =
contention.</div></div></div><br><blockquote type=3D"cite"><div =
bgcolor=3D"#ffffff" style=3D"word-wrap: break-word; -webkit-nbsp-mode: =
space; -webkit-line-break: after-white-space; "><div><font =
size=3D"2">&nbsp;&nbsp;&nbsp; To swallow the above (no pun intended) you =
have to accept that--</font></div><div><font size=3D"2">1) Beetles and =
true bugs constitute the Swift's&nbsp;diet almost =
entirely,</font></div></div></blockquote><div><br></div><div>The data =
presented in Figures 2(a) &amp; 2(b) shows that this appears to be =
so.</div><br><blockquote type=3D"cite"><span class=3D"Apple-style-span" =
style=3D"border-collapse: separate; color: rgb(0, 0, 0); font-family: =
'Times New Roman'; font-style: normal; font-variant: normal; =
font-weight: normal; letter-spacing: normal; line-height: normal; =
orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: =
none; white-space: normal; widows: 2; word-spacing: 0px; =
-webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: =
0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
bgcolor=3D"#ffffff" style=3D"word-wrap: break-word; -webkit-nbsp-mode: =
space; -webkit-line-break: after-white-space; "><div><font size=3D"2">2) =
A questionably significant decrease in relative abundance of Beetle =
debris from 0.6 to 0.4 contributed to a 90% decline in Swift population =
and</font></div></div></span></blockquote><div><br></div><div>No, =
incorrect. As the full sentence above makes clear, dietary change is =
only&nbsp;one of several factors contributing to the =
decline.</div><br><blockquote type=3D"cite"><span =
class=3D"Apple-style-span" style=3D"border-collapse: separate; color: =
rgb(0, 0, 0); font-family: 'Times New Roman'; font-style: normal; =
font-variant: normal; font-weight: normal; letter-spacing: normal; =
line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: =
0px; text-transform: none; white-space: normal; widows: 2; word-spacing: =
0px; -webkit-border-horizontal-spacing: 0px; =
-webkit-border-vertical-spacing: 0px; =
-webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
bgcolor=3D"#ffffff" style=3D"word-wrap: break-word; -webkit-nbsp-mode: =
space; -webkit-line-break: after-white-space; "><div><font size=3D"2">3) =
Essentially the same decrease in Beetle relative abundance would be =
found in roosts throughout the range of Chimney =
Swifts.</font></div></div></span></blockquote><br></div></div><div>The =
author's make no such claim in the paper, nor do I believe they would =
argue this, nor is this a necessary assumption to any of their =
conclusions. If this study were to be replicated elsewhere, relative =
Coleoptera abundance might be similar or different, and population =
declines in swifts at that site might, again be similar or different. =
Such a study would need to be undertaken to determine both of =
these.</div><div><br></div><div>Truncating the second sentence of the =
fourth paragraph of the discussion completely alters its meaning and =
leads you to draw incorrect assumptions about what the study is =
predicated on and =
implies.</div><div><br></div><div>Cheers!</div><div><br></div><div>Chris</=
div><br><br><div apple-content-edited=3D"true"> <span =
class=3D"Apple-style-span" style=3D"border-collapse: separate; color: =
rgb(0, 0, 0); font-family: 'Times New Roman'; font-style: normal; =
font-variant: normal; font-weight: normal; letter-spacing: normal; =
line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; =
text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; =
-webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: =
0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; =
-webkit-line-break: after-white-space; "><span class=3D"Apple-style-span" =
style=3D"border-collapse: separate; color: rgb(0, 0, 0); font-family: =
'Times New Roman'; font-style: normal; font-variant: normal; =
font-weight: normal; letter-spacing: normal; line-height: normal; =
orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; =
widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; =
-webkit-border-vertical-spacing: 0px; =
-webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; =
-webkit-line-break: after-white-space; "><span class=3D"Apple-style-span" =
style=3D"border-collapse: separate; color: rgb(0, 0, 0); font-family: =
'Times New Roman'; font-style: normal; font-variant: normal; =
font-weight: normal; letter-spacing: normal; line-height: normal; =
orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; =
widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; =
-webkit-border-vertical-spacing: 0px; =
-webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; =
-webkit-line-break: after-white-space; "><span class=3D"Apple-style-span" =
style=3D"border-collapse: separate; color: rgb(0, 0, 0); font-family: =
'Times New Roman'; font-style: normal; font-variant: normal; =
font-weight: normal; letter-spacing: normal; line-height: normal; =
orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; =
widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; =
-webkit-border-vertical-spacing: 0px; =
-webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; =
-webkit-line-break: after-white-space; "><span class=3D"Apple-style-span" =
style=3D"border-collapse: separate; color: rgb(0, 0, 0); font-family: =
'Times New Roman'; font-style: normal; font-variant: normal; =
font-weight: normal; letter-spacing: normal; line-height: normal; =
orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; =
widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; =
-webkit-border-vertical-spacing: 0px; =
-webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: =
auto; -webkit-text-stroke-width: 0px; font-size: medium; "><div =
style=3D"word-wrap: break-word; -webkit-nbsp-mode: space; =
-webkit-line-break: after-white-space; =
"><div><div><div><div><div><div><div><div><font class=3D"Apple-style-span"=
 size=3D"3"><span class=3D"Apple-style-span" style=3D"font-size: 12px; =
">Christopher Majka &nbsp;&lt;<a =
href=3D"mailto:c.majka@ns.sympatico.ca">c.majka@ns.sympatico.ca</a>&gt; =
|&nbsp;Halifax, Nova Scotia, Canada</span></font></div><div><font =
class=3D"Apple-style-span" size=3D"3"><span class=3D"Apple-style-span" =
style=3D"font-size: 12px; "><br></span></font></div><div><font =
class=3D"Apple-style-span" size=3D"3"><span class=3D"Apple-style-span" =
style=3D"font-size: 12px; ">* Research Associate: Nova Scotia Museum =
|&nbsp;<a =
href=3D"http://museum.gov.ns.ca/mnh/research-asfr.htm">http://museum.gov.n=
s.ca/mnh/research-asfr.htm</a></span></font></div><div><font =
class=3D"Apple-style-span" size=3D"3"><span class=3D"Apple-style-span" =
style=3D"font-size: 12px; ">* Review Editor: The Coleopterists Bulletin =
|&nbsp;<a =
href=3D"http://www.coleopsoc.org/">http://www.coleopsoc.org/</a></span></f=
ont></div><div><font class=3D"Apple-style-span" size=3D"3"><span =
class=3D"Apple-style-span" style=3D"font-size: 12px; ">* Subject Editor: =
ZooKeys |&nbsp;<a =
href=3D"http://pensoftonline.net/zookeys/index.php/journal/index">http://p=
ensoftonline.net/zookeys/index.php/journal/index</a></span></font></div><d=
iv><font class=3D"Apple-style-span" size=3D"3"><span =
class=3D"Apple-style-span" style=3D"font-size: 12px; ">* Review Editor: =
Zootaxa |&nbsp;<a =
href=3D"http://www.mapress.com/zootaxa/taxa/Coleoptera.html">http://www.ma=
press.com/zootaxa/taxa/Coleoptera.html</a></span></font></div><div><font =
class=3D"Apple-style-span" size=3D"3"><span class=3D"Apple-style-span" =
style=3D"font-size: 12px; ">* Associate Editor: Journal of the Acadian =
Entomological Society |&nbsp;<a =
href=3D"http://www.acadianes.org/journal.html">http://www.acadianes.org/jo=
urnal.html</a></span></font></div><div><font class=3D"Apple-style-span" =
size=3D"3"><span class=3D"Apple-style-span" style=3D"font-size: 12px; =
">* Editor: Atlantic Canada Coleoptera |&nbsp;<a =
href=3D"http://www.chebucto.ns.ca/Environment/NHR/PDF/index.html">http://w=
ww.chebucto.ns.ca/Environment/NHR/PDF/index.html</a></span></font></div><d=
iv><font class=3D"Apple-style-span" size=3D"3"><span =
class=3D"Apple-style-span" style=3D"font-size: 12px; ">* Editor: =
Bugguide, Coleoptera&nbsp;<a =
href=3D"http://bugguide.net">http://bugguide.net</a></span></font></div><d=
iv><font class=3D"Apple-style-span" size=3D"3"><span =
class=3D"Apple-style-span" style=3D"font-size: 12px; =
"><br></span></font></div><div><i><font class=3D"Apple-style-span" =
size=3D"3"><span class=3D"Apple-style-span" style=3D"font-size: 12px; =
">Whenever I hear of the capture of rare&nbsp;beetles, I feel like an =
old war-horse at the sound of a trumpet.</span></font></i><span =
class=3D"Apple-converted-space"><font class=3D"Apple-style-span" =
size=3D"3"><span class=3D"Apple-style-span" style=3D"font-size: 12px; =
">&nbsp;</span></font></span><font class=3D"Apple-style-span" =
size=3D"3"><span class=3D"Apple-style-span" style=3D"font-size: 12px; =
">- =
Charles&nbsp;Darwin</span></font></div></div></div></div></div></div></div=
></div></div></span></div></span></div></span></div></span></div></span> =
</div><br></body></html>=

--Apple-Mail-79-514812118--

next message in archive
no next message in thread
previous message in archive
previous message in thread
Index of Subjects