A Model For Sea Lice ( Lepeophtheirus salmonis ) Dynamics In A Seasonally Changing Environment

Highlights • We incorporate temperature and salinity into a model of sea lice development. • We show different annual reproductive peaks between British Columbia and Newfoundland. • We find the model is more sensitive to environmental than to biological parameters. • Consideration of local environme...

Full description

Saved in:
Bibliographic Details
Published in:Epidemics Vol. 16; no. C; pp. 8 - 16
Main Authors: Rittenhouse, Matthew A, Revie, Crawford W, Hurford, Amy
Format: Journal Article
Language:English
Published: Netherlands Elsevier B.V 01-09-2016
Elsevier
Subjects:
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Abstract Highlights • We incorporate temperature and salinity into a model of sea lice development. • We show different annual reproductive peaks between British Columbia and Newfoundland. • We find the model is more sensitive to environmental than to biological parameters. • Consideration of local environmental patterns can improve sea lice management.
AbstractList Sea lice (Lepeophtheirus salmonis) are a significant source of monetary losses on salmon farms. Sea lice exhibit temperature-dependent development rates and salinity-dependent mortality, but to date no deterministic models have incorporated these seasonally varying factors. To understand how environmental variation and life history characteristics affect sea lice abundance, we derive a delay differential equation model and parameterize the model with environmental data from British Columbia and southern Newfoundland. We calculate the lifetime reproductive output for female sea lice maturing to adulthood at different times of the year and find differences in the timing of peak reproduction between the two regions. Using a sensitivity analysis, we find that sea lice abundance is more sensitive to variation in mean annual water temperature and mean annual salinity than to variation in life history parameters. Our results suggest that effective sea lice management requires consideration of site-specific temperature and salinity patterns and, in particular, that the optimal timing of production cycles and sea lice treatments might vary between regions.
•We incorporate temperature and salinity into a model of sea lice development.•We show different annual reproductive peaks between British Columbia and Newfoundland.•We find the model is more sensitive to environmental than to biological parameters.•Consideration of local environmental patterns can improve sea lice management. Sea lice (Lepeophtheirus salmonis) are a significant source of monetary losses on salmon farms. Sea lice exhibit temperature-dependent development rates and salinity-dependent mortality, but to date no deterministic models have incorporated these seasonally varying factors. To understand how environmental variation and life history characteristics affect sea lice abundance, we derive a delay differential equation model and parameterize the model with environmental data from British Columbia and southern Newfoundland. We calculate the lifetime reproductive output for female sea lice maturing to adulthood at different times of the year and find differences in the timing of peak reproduction between the two regions. Using a sensitivity analysis, we find that sea lice abundance is more sensitive to variation in mean annual water temperature and mean annual salinity than to variation in life history parameters. Our results suggest that effective sea lice management requires consideration of site-specific temperature and salinity patterns and, in particular, that the optimal timing of production cycles and sea lice treatments might vary between regions.
Highlights • We incorporate temperature and salinity into a model of sea lice development. • We show different annual reproductive peaks between British Columbia and Newfoundland. • We find the model is more sensitive to environmental than to biological parameters. • Consideration of local environmental patterns can improve sea lice management.
Author Revie, Crawford W
Hurford, Amy
Rittenhouse, Matthew A
Author_xml – sequence: 1
  fullname: Rittenhouse, Matthew A
– sequence: 2
  fullname: Revie, Crawford W
– sequence: 3
  fullname: Hurford, Amy
BackLink https://www.ncbi.nlm.nih.gov/pubmed/27663786$$D View this record in MEDLINE/PubMed
BookMark eNqFUk1v1DAQjVAR_YB_gJCP5ZDFH4mTXJBW2xZWWsShcMWaOONdL4kd7Gyl_fc4bNtDL5xsj9574zdvLrMz5x1m2XtGF4wy-Wm_wNF2OCx4ei2oWFAqXmUXrK7qnFJZnaV7VZZ5IWR5nl3GuE_VgjHxJjvnlZSiquVF9mtJvvkOe3LnA7lHIBurkVyTDY7ox920QxsOkUToB-9sJB_JzdHBYHUka0eWMyV6B31_JKsduK11W3LrHmzwbkA3vc1eG-gjvns8r7Kfd7c_Vl_zzfcv69Vyk-uSN1NemhZ1-j9nghcFYNUapkFUTQEGBMeyZRRrKXkHuikMkzU1pekk8k60rCnFVbY-6XYe9moMdoBwVB6s-lfwYasgTFb3qLipuTEtQNeYoqoFQE0ZawQzsmnamiat65PWGPyfA8ZJDTZq7Htw6A9RsZoLmoZaygQtTlAdfIwBzXNrRtWcktqrU0pqTklRoZLLRPvw2OHQDtg9k55iSYDPJwCmmT1YDCpqi05jZwPqKZmy_-vwUkD31lkN_W88Ytz7Q0ihJS8qckXV_bwp86IwKWiaBhN_AbCmueQ
CitedBy_id crossref_primary_10_1002_ece3_10027
crossref_primary_10_1016_j_prevetmed_2020_104985
crossref_primary_10_1016_j_epidem_2017_11_001
crossref_primary_10_3354_dao03329
crossref_primary_10_1098_rspb_2019_0428
crossref_primary_10_1111_jfd_12931
crossref_primary_10_1111_jfd_13504
crossref_primary_10_1016_j_aquaculture_2017_12_017
crossref_primary_10_1111_raq_12625
crossref_primary_10_1007_s11538_021_00923_2
crossref_primary_10_1016_j_ecolmodel_2017_05_019
crossref_primary_10_3354_aei00320
crossref_primary_10_3354_aei00324
crossref_primary_10_1139_cjfas_2023_0070
crossref_primary_10_3354_aei00469
crossref_primary_10_3389_fmars_2021_763206
crossref_primary_10_1016_j_ecolmodel_2020_109258
crossref_primary_10_1111_jfd_12742
crossref_primary_10_3354_dao03731
crossref_primary_10_1007_s11538_018_0440_4
crossref_primary_10_1016_j_pt_2018_09_007
crossref_primary_10_1111_jfd_13535
crossref_primary_10_1007_s11538_018_0447_x
crossref_primary_10_1016_j_aquaculture_2021_737246
crossref_primary_10_1371_journal_pclm_0000017
crossref_primary_10_1007_s11538_017_0276_3
crossref_primary_10_1016_j_aquaculture_2021_736792
crossref_primary_10_3354_meps13664
crossref_primary_10_1016_j_aquaculture_2016_08_002
crossref_primary_10_1016_j_epidem_2018_04_002
crossref_primary_10_1093_icesjms_fsac202
crossref_primary_10_1111_raq_12274
crossref_primary_10_1139_cjfas_2020_0160
crossref_primary_10_1654_1525_2647_85_1_1
crossref_primary_10_1016_j_nonrwa_2018_05_007
Cites_doi 10.1371/journal.pone.0073539
10.1016/j.epidem.2014.09.007
10.1371/journal.pone.0079276
10.3354/dao02517
10.1111/j.1095-8649.2008.01839.x
10.1111/j.1365-2761.2012.01415.x
10.1098/rspb.2011.2210
10.3354/dao071201
10.1016/j.aquaculture.2010.05.006
10.1111/j.1365-2761.2005.00665.x
10.2307/1403510
10.1098/rsif.2005.0042
10.1111/jfd.12018
10.1016/j.aquaculture.2011.03.017
10.1111/j.1365-2761.2008.00969.x
10.1371/journal.pone.0139128
10.3354/meps290263
10.1111/j.1365-2761.2010.01192.x
10.1016/j.ijpara.2015.03.006
10.1007/s10126-008-9112-y
10.1111/j.1365-2761.2008.01011.x
10.1098/rspb.2012.0084
10.1016/j.pt.2007.12.010
10.1371/journal.pone.0064039
10.1111/j.1461-0248.2005.00879.x
10.1080/10641260500448893
10.1016/0040-5809(83)90008-4
10.1017/S0025315400051687
10.1073/pnas.1009573108
10.1371/journal.pone.0088465
10.1016/j.jtbi.2010.12.004
10.1046/j.1365-2109.2000.00512.x
10.1086/664458
10.1016/j.jtbi.2008.04.011
10.1186/1471-2156-15-32
ContentType Journal Article
Copyright 2016 The Authors
Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Copyright_xml – notice: 2016 The Authors
– notice: Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
DBID 6I.
AAFTH
CGR
CUY
CVF
ECM
EIF
NPM
AAYXX
CITATION
7X8
DOA
DOI 10.1016/j.epidem.2016.03.003
DatabaseName ScienceDirect Open Access Titles
Elsevier:ScienceDirect:Open Access
Medline
MEDLINE
MEDLINE (Ovid)
MEDLINE
MEDLINE
PubMed
CrossRef
MEDLINE - Academic
Directory of Open Access Journals
DatabaseTitle MEDLINE
Medline Complete
MEDLINE with Full Text
PubMed
MEDLINE (Ovid)
CrossRef
MEDLINE - Academic
DatabaseTitleList
MEDLINE
MEDLINE - Academic


Database_xml – sequence: 1
  dbid: DOA
  name: Directory of Open Access Journals
  url: http://www.doaj.org/
  sourceTypes: Open Website
– sequence: 2
  dbid: ECM
  name: MEDLINE
  url: https://search.ebscohost.com/login.aspx?direct=true&db=cmedm&site=ehost-live
  sourceTypes: Index Database
DeliveryMethod fulltext_linktorsrc
Discipline Public Health
EISSN 1878-0067
EndPage 16
ExternalDocumentID oai_doaj_org_article_2f82ffbaad9f4783aa8011931f699b80
10_1016_j_epidem_2016_03_003
27663786
S1755436516300111
1_s2_0_S1755436516300111
Genre Journal Article
GroupedDBID ---
--K
.1-
.FO
.~1
0R~
0SF
1B1
1P~
1~.
4.4
457
4G.
53G
5GY
5VS
7-5
71M
8P~
AACTN
AAEDW
AAIKJ
AALRI
AAQFI
AARKO
AAXUO
ABBQC
ABGSF
ABMAC
ABXDB
ACGFS
ADBBV
ADEZE
ADMUD
ADQTV
ADUVX
ADVLN
AEKER
AENEX
AEQOU
AEVXI
AEXQZ
AFCTW
AFJKZ
AFRHN
AFTJW
AGEKW
AGHFR
AGYEJ
AITUG
AJOXV
AJRQY
AJUYK
AKRWK
ALMA_UNASSIGNED_HOLDINGS
AMRAJ
BCNDV
EBS
EJD
EP2
EP3
F5P
FDB
FEDTE
FIRID
FNPLU
GBLVA
GROUPED_DOAJ
HVGLF
HZ~
IPNFZ
IXB
J1W
KQ8
LUGTX
M41
M48
MO0
N9A
NCXOZ
O-L
O9-
OD-
OK1
OO.
OZT
P-8
P-9
PC.
Q38
RIG
ROL
SDF
SES
SSZ
Z5R
6I.
AAFTH
CBWCG
DOVZS
LCYCR
CGR
CUY
CVF
ECM
EIF
NPM
AAYXX
CITATION
7X8
ID FETCH-LOGICAL-c529t-5fbec003213244ae7bf1ca3794afa32e5b10e8662dac94f1680f5fd6e2d3b1953
IEDL.DBID DOA
ISSN 1755-4365
IngestDate Tue Oct 22 15:04:32 EDT 2024
Fri Oct 25 00:13:58 EDT 2024
Thu Sep 26 19:54:18 EDT 2024
Wed Oct 16 00:57:20 EDT 2024
Mon Apr 15 08:35:54 EDT 2024
Tue Oct 15 22:54:10 EDT 2024
IsDoiOpenAccess true
IsOpenAccess true
IsPeerReviewed true
IsScholarly true
Issue C
Keywords Sea lice
Mathematical model
Delay differential equations
Seasonality
Aquaculture
Language English
License This is an open access article under the CC BY license.
Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
LinkModel DirectLink
MergedId FETCHMERGED-LOGICAL-c529t-5fbec003213244ae7bf1ca3794afa32e5b10e8662dac94f1680f5fd6e2d3b1953
Notes ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 23
OpenAccessLink https://doaj.org/article/2f82ffbaad9f4783aa8011931f699b80
PMID 27663786
PQID 1823036556
PQPubID 23479
PageCount 9
ParticipantIDs doaj_primary_oai_doaj_org_article_2f82ffbaad9f4783aa8011931f699b80
proquest_miscellaneous_1823036556
crossref_primary_10_1016_j_epidem_2016_03_003
pubmed_primary_27663786
elsevier_sciencedirect_doi_10_1016_j_epidem_2016_03_003
elsevier_clinicalkeyesjournals_1_s2_0_S1755436516300111
PublicationCentury 2000
PublicationDate 2016-09-01
PublicationDateYYYYMMDD 2016-09-01
PublicationDate_xml – month: 09
  year: 2016
  text: 2016-09-01
  day: 01
PublicationDecade 2010
PublicationPlace Netherlands
PublicationPlace_xml – name: Netherlands
PublicationTitle Epidemics
PublicationTitleAlternate Epidemics
PublicationYear 2016
Publisher Elsevier B.V
Elsevier
Publisher_xml – name: Elsevier B.V
– name: Elsevier
References Altizer, Dobson, Hosseini, Hudson, Pascual, Rohani (bib0010) 2006; 9
Stien, Bjørn, Heuch, Elston (bib0190) 2005; 290
Groner, Gettinby, Stormoen, Revie, Cox (bib0065) 2014; 9
Heuch, Nordhagen, Schram (bib0080) 2000; 31
Jones, Hammell, Dohoo, Revie (bib0095) 2012; 102
Krkošek, Connors, Lewis, Poulin (bib0110) 2012; 179
Samsing, Solstorm, Oppedal, Solstorm, Dempster (bib0175) 2015; 45
Marino, Hogue, Ray, Kirschner (bib0120) 2008; 254
Marty, Saksida, Quinn (bib0125) 2010; 107
McEwan, Groner, Fast, Gettinby, Revie (bib0130) 2015; 10
Hamre, Eichner, Caipang, Dalvin, Bron, Nilsen, Boxshall, Skern-Mauritzen (bib0070) 2013; 8
Wagner, Fast, Johnson (bib0200) 2008; 24
Jansen, Kristoffersen, Viljugrein, Jiminez, Aldrin, Stien (bib0085) 2012; 279
Beamish, Jones (bib0015) 2011
Heffernan, Smith, Wahl (bib0075) 2005; 2
Robbins, Gettinby, Lees, Baillie, Wallace, Revie (bib0160) 2010; 306
Sevatdal (bib0180) 2001; 21
Saksida, Morrison, Revie (bib0165) 2010; 33
Gettinby, Robbins, Lees, Heuch, Finstad, Malkenes, Revie (bib0060) 2011; 320
Johnson, Albright (bib0090) 1991; 71
Kristoffersen, Jimenez, Hildegunn, Grøntvedt, Stien, Jansen (bib0105) 2014; 9
Omori, Adams (bib0145) 2010; 271
Ritchie, Mordue, Pike, Rae (bib0155) 1993
Connors, Juarez-Colunga, Dill (bib0045) 2008; 72
Frazer, Morton, Krkošek (bib0055) 2012; 279
Revie, Robbins, Gettinby, Kelly, Treasurer (bib0150) 2005; 28
Stormoen, Skjerve, Aunsmo (bib0195) 2013; 36
Beck-Johnson, Nelson, Paajimans, Read, Thomas, Bjørnstad (bib0020) 2014; 8
Aldrin, Storvik, Kristoffersen, Jansen, Krkošek (bib0005) 2013; 8
Bricknell, Dalesman, O'Shea, Pert, Mordue Luntz (bib0035) 2006; 71
Mustafa, Conboy, Burka (bib0135) 2000; 4
Lees, Baillie, Gettinby, Revie (bib0115) 2008; 31
Saksida, Morrison, McKenzie, Milligan, Downey, Boyce, Eaves (bib0170) 2013; 36
Costello (bib0050) 2009; 32
Yazawa, Yasuike, Leong, von Schalburg, Cooper, Beetz-Sargent, Robb, Davidson, Jones, Koop (bib0205) 2008; 10
Zhao (bib0210) 2015
Blower, Dowlatabadi (bib0025) 1994; 62
Skern-Mauritzen, Torrissen, Glover (bib0185) 2014; 15
Nisbet, Gurney (bib0140) 1983; 23
Jones, Mead, Kaiser, Austen, Adrian, Auchterlonie, Black, Blow, Bury, Brown, Burnell, Connolly, Dingwall, Derrick, Eno, Gautier, Green, Gubbins, Hart, Holmyard, Immink, Jarrad, Katoh, Langley, Lee, Le Vay, Leftwich, Mitchell, Moore, Murray, McLaren, Norbury, Parker, Parry, Purchase, Rahman, Sanver, Siggs, Simpson, Slaski, Smith, Syvret, Tibbott, Thomas, Turnbull, Whitely, Whittles, Wilcockson, Wilson, Dicks, Sutherland (bib0100) 2014
Brooks, Stucchi (bib0040) 2006; 14
Jones (10.1016/j.epidem.2016.03.003_bib0100) 2014
Saksida (10.1016/j.epidem.2016.03.003_bib0165) 2010; 33
Mustafa (10.1016/j.epidem.2016.03.003_bib0135) 2000; 4
Zhao (10.1016/j.epidem.2016.03.003_bib0210) 2015
Johnson (10.1016/j.epidem.2016.03.003_bib0090) 1991; 71
Aldrin (10.1016/j.epidem.2016.03.003_bib0005) 2013; 8
Saksida (10.1016/j.epidem.2016.03.003_bib0170) 2013; 36
Samsing (10.1016/j.epidem.2016.03.003_bib0175) 2015; 45
Revie (10.1016/j.epidem.2016.03.003_bib0150) 2005; 28
Nisbet (10.1016/j.epidem.2016.03.003_bib0140) 1983; 23
Frazer (10.1016/j.epidem.2016.03.003_bib0055) 2012; 279
Blower (10.1016/j.epidem.2016.03.003_bib0025) 1994; 62
Heuch (10.1016/j.epidem.2016.03.003_bib0080) 2000; 31
Groner (10.1016/j.epidem.2016.03.003_bib0065) 2014; 9
Kristoffersen (10.1016/j.epidem.2016.03.003_bib0105) 2014; 9
Jones (10.1016/j.epidem.2016.03.003_bib0095) 2012; 102
Hamre (10.1016/j.epidem.2016.03.003_bib0070) 2013; 8
Omori (10.1016/j.epidem.2016.03.003_bib0145) 2010; 271
Brooks (10.1016/j.epidem.2016.03.003_bib0040) 2006; 14
McEwan (10.1016/j.epidem.2016.03.003_bib0130) 2015; 10
Altizer (10.1016/j.epidem.2016.03.003_bib0010) 2006; 9
Robbins (10.1016/j.epidem.2016.03.003_bib0160) 2010; 306
Beck-Johnson (10.1016/j.epidem.2016.03.003_bib0020) 2014; 8
Krkošek (10.1016/j.epidem.2016.03.003_bib0110) 2012; 179
Wagner (10.1016/j.epidem.2016.03.003_bib0200) 2008; 24
Gettinby (10.1016/j.epidem.2016.03.003_bib0060) 2011; 320
Lees (10.1016/j.epidem.2016.03.003_bib0115) 2008; 31
Marty (10.1016/j.epidem.2016.03.003_bib0125) 2010; 107
Skern-Mauritzen (10.1016/j.epidem.2016.03.003_bib0185) 2014; 15
Beamish (10.1016/j.epidem.2016.03.003_bib0015) 2011
Connors (10.1016/j.epidem.2016.03.003_bib0045) 2008; 72
Marino (10.1016/j.epidem.2016.03.003_bib0120) 2008; 254
Stien (10.1016/j.epidem.2016.03.003_bib0190) 2005; 290
Yazawa (10.1016/j.epidem.2016.03.003_bib0205) 2008; 10
Jansen (10.1016/j.epidem.2016.03.003_bib0085) 2012; 279
Heffernan (10.1016/j.epidem.2016.03.003_bib0075) 2005; 2
Stormoen (10.1016/j.epidem.2016.03.003_bib0195) 2013; 36
Ritchie (10.1016/j.epidem.2016.03.003_bib0155) 1993
Costello (10.1016/j.epidem.2016.03.003_bib0050) 2009; 32
Sevatdal (10.1016/j.epidem.2016.03.003_bib0180) 2001; 21
Bricknell (10.1016/j.epidem.2016.03.003_bib0035) 2006; 71
References_xml – volume: 9
  start-page: 467
  year: 2006
  end-page: 484
  ident: bib0010
  article-title: Seasonality and the dynamics of infectious diseases: seasonality and infectious diseases
  publication-title: Ecol. Lett.
  contributor:
    fullname: Rohani
– volume: 62
  start-page: 229
  year: 1994
  end-page: 243
  ident: bib0025
  article-title: Sensitivity and uncertainty analysis of complex models of disease transmission: an HIV model, as an example
  publication-title: Int. Stat. Rev. [Revue Internationale de Statistique]
  contributor:
    fullname: Dowlatabadi
– volume: 290
  start-page: 263
  year: 2005
  end-page: 275
  ident: bib0190
  article-title: Population dynamics of salmon lice
  publication-title: Mar. Ecol. Prog. Ser.
  contributor:
    fullname: Elston
– volume: 279
  start-page: 1950
  year: 2012
  end-page: 1958
  ident: bib0055
  article-title: Critical thresholds in sea lice epidemics: evidence, sensitivity and subcritical estimation
  publication-title: Proc. R. Soc. B: Biol. Sci.
  contributor:
    fullname: Krkošek
– volume: 32
  start-page: 115
  year: 2009
  end-page: 118
  ident: bib0050
  article-title: The global economic cost of sea lice to the salmonid farming industry
  publication-title: J. Fish Dis.
  contributor:
    fullname: Costello
– volume: 9
  start-page: e88465
  year: 2014
  ident: bib0065
  article-title: Modelling the impact of temperature-induced life history plasticity and mate limitation on the epidemic potential of a marine ectoparasite
  publication-title: PLOS ONE
  contributor:
    fullname: Cox
– volume: 31
  start-page: 805
  year: 2000
  end-page: 814
  ident: bib0080
  article-title: Egg production in the salmon louse [
  publication-title: Aquac. Res.
  contributor:
    fullname: Schram
– volume: 28
  start-page: 603
  year: 2005
  end-page: 613
  ident: bib0150
  article-title: A mathematical model of the growth of sea lice,
  publication-title: J. Fish Dis.
  contributor:
    fullname: Treasurer
– volume: 24
  start-page: 176
  year: 2008
  end-page: 183
  ident: bib0200
  article-title: Physiology and immunology of
  publication-title: Trends Parasitol.
  contributor:
    fullname: Johnson
– volume: 8
  start-page: e79276
  year: 2014
  ident: bib0020
  article-title: The effect of temperature on anopheles mosquito population dynamics and the potential for malaria transmission
  publication-title: PLOS ONE
  contributor:
    fullname: Bjørnstad
– volume: 2
  start-page: 281
  year: 2005
  end-page: 293
  ident: bib0075
  article-title: Perspectives on the basic reproductive ratio
  publication-title: J. R. Soc. Interface
  contributor:
    fullname: Wahl
– volume: 179
  start-page: 401
  year: 2012
  end-page: 412
  ident: bib0110
  article-title: Allee effects may slow the spread of parasites in a coastal marine ecosystem
  publication-title: Am. Nat.
  contributor:
    fullname: Poulin
– volume: 31
  start-page: 947
  year: 2008
  end-page: 951
  ident: bib0115
  article-title: Factors associated with changing efficacy of emamectin benzoate against infestations of
  publication-title: J. Fish Dis.
  contributor:
    fullname: Revie
– volume: 45
  start-page: 559
  year: 2015
  end-page: 565
  ident: bib0175
  article-title: Gone with the flow: current velocities mediate parasitic infestation of an aquatic host
  publication-title: Int. J. Parasitol.
  contributor:
    fullname: Dempster
– volume: 8
  start-page: e64039
  year: 2013
  ident: bib0005
  article-title: Space-time modelling of the spread of salmon lice between and within Norwegian marine salmon farms
  publication-title: PLoS ONE
  contributor:
    fullname: Krkošek
– volume: 306
  start-page: 191
  year: 2010
  end-page: 197
  ident: bib0160
  article-title: Assessing topical treatment interventions on Scottish salmon farms using a sea lice (
  publication-title: Aquaculture
  contributor:
    fullname: Revie
– volume: 107
  start-page: 22599
  year: 2010
  end-page: 22604
  ident: bib0125
  article-title: Relationship of farm salmon, sea lice, and wild salmon populations
  publication-title: Proc. Natl. Acad. Sci. U. S. A.
  contributor:
    fullname: Quinn
– year: 2014
  ident: bib0100
  article-title: Prioritization of knowledge needs for sustainable aquaculture: a national and global perspective
  publication-title: Fish Fish.
  contributor:
    fullname: Sutherland
– volume: 9
  start-page: 31
  year: 2014
  end-page: 39
  ident: bib0105
  article-title: Large scale modelling of salmon lice (
  publication-title: Epidemics
  contributor:
    fullname: Jansen
– volume: 33
  start-page: 913
  year: 2010
  end-page: 917
  ident: bib0165
  article-title: The efficacy of emamectin benzoate against infestations of sea lice,
  publication-title: J. Fish Dis.
  contributor:
    fullname: Revie
– volume: 279
  start-page: 2330
  year: 2012
  end-page: 2338
  ident: bib0085
  article-title: Sea lice as a density-dependent constraint to salmonid farming
  publication-title: Proc. R. Soc. B: Biol. Sci.
  contributor:
    fullname: Stien
– volume: 10
  start-page: 741
  year: 2008
  end-page: 749
  ident: bib0205
  article-title: EST and mitochondrial DNA sequences support a distinct pacific form of salmon louse,
  publication-title: Mar. Biotechnol.
  contributor:
    fullname: Koop
– volume: 102
  start-page: 53
  year: 2012
  end-page: 64
  ident: bib0095
  article-title: Effectiveness of emamectin benzoate for treatment of
  publication-title: Dis. Aquat. Organ.
  contributor:
    fullname: Revie
– volume: 4
  start-page: 113
  year: 2000
  end-page: 114
  ident: bib0135
  article-title: Lifespan and reproductive capacity of sea lice, (
  publication-title: Aquac. Assoc. Can.
  contributor:
    fullname: Burka
– volume: 15
  start-page: 32
  year: 2014
  ident: bib0185
  article-title: Pacific and Atlantic
  publication-title: BMC Genetics
  contributor:
    fullname: Glover
– volume: 10
  start-page: e0139128
  year: 2015
  ident: bib0130
  article-title: Using agent-based modelling to predict the role of wild refugia in the evolution of resistance of sea lice to chemotherapeutants
  publication-title: PLoS ONE
  contributor:
    fullname: Revie
– start-page: 1
  year: 2015
  end-page: 16
  ident: bib0210
  article-title: Basic reproduction ratios for periodic compartment models with time delay
  publication-title: J. Dyn. Differ. Equ.
  contributor:
    fullname: Zhao
– volume: 71
  start-page: 201
  year: 2006
  end-page: 212
  ident: bib0035
  article-title: Effect of environmental salinity on sea lice
  publication-title: Dis. Aquat. Organ.
  contributor:
    fullname: Mordue Luntz
– volume: 271
  start-page: 159
  year: 2010
  end-page: 165
  ident: bib0145
  article-title: Disrupting seasonality to control diseases outbreaks: the case of koi herpes virus
  publication-title: J. Theor. Biol.
  contributor:
    fullname: Adams
– start-page: 153
  year: 1993
  end-page: 165
  ident: bib0155
  article-title: The reproductive output of
  publication-title: Pathogens of Wild and Farmed Fish: Sea Lice
  contributor:
    fullname: Rae
– volume: 71
  start-page: 425
  year: 1991
  end-page: 436
  ident: bib0090
  article-title: Development, growth, and survival of
  publication-title: J. Mar. Biol. Assoc. U. K.
  contributor:
    fullname: Albright
– year: 2011
  ident: bib0015
  article-title: Salmon Lice: An Integrated Approach to Understanding Parasite Abundance and Distribution
  contributor:
    fullname: Jones
– volume: 23
  start-page: 114
  year: 1983
  end-page: 135
  ident: bib0140
  article-title: The systematic formulation of population models for insects with dynamically varying instar duration
  publication-title: Theor. Popul. Biol.
  contributor:
    fullname: Gurney
– volume: 320
  start-page: 164
  year: 2011
  end-page: 170
  ident: bib0060
  article-title: Use of a mathematical model to describe the epidemiology of
  publication-title: Aquaculture
  contributor:
    fullname: Revie
– volume: 254
  start-page: 178
  year: 2008
  end-page: 196
  ident: bib0120
  article-title: A methodology for performing global uncertainty and sensitivity analysis in systems biology
  publication-title: J. Theor. Biol.
  contributor:
    fullname: Kirschner
– volume: 36
  start-page: 25
  year: 2013
  end-page: 33
  ident: bib0195
  article-title: Modelling salmon lice,
  publication-title: J. Fish Dis.
  contributor:
    fullname: Aunsmo
– volume: 8
  start-page: e73539
  year: 2013
  ident: bib0070
  article-title: The salmon louse
  publication-title: PLoS ONE
  contributor:
    fullname: Skern-Mauritzen
– volume: 72
  start-page: 1825
  year: 2008
  end-page: 1830
  ident: bib0045
  article-title: Effects of varying salinities on
  publication-title: J. Fish Biol.
  contributor:
    fullname: Dill
– volume: 36
  start-page: 515
  year: 2013
  end-page: 520
  ident: bib0170
  article-title: Use of Atlantic salmon,
  publication-title: J. Fish Dis.
  contributor:
    fullname: Eaves
– volume: 14
  start-page: 13
  year: 2006
  end-page: 23
  ident: bib0040
  article-title: The effects of water temperature, salinity, and currents, on the survival and distribution of the infective copepodid stage of the salmon louse (
  publication-title: Rev. Fish. Sci.
  contributor:
    fullname: Stucchi
– volume: 21
  start-page: 109
  year: 2001
  end-page: 113
  ident: bib0180
  article-title: An improved method for experimental infection of salmon (
  publication-title: Bull. Eur. Assoc. Fish Patholog.
  contributor:
    fullname: Sevatdal
– volume: 8
  start-page: e73539
  year: 2013
  ident: 10.1016/j.epidem.2016.03.003_bib0070
  article-title: The salmon louse Lepeophtheirus salmonis (Copepoda: Caligidae) life cycle has only two Chalimus stages
  publication-title: PLoS ONE
  doi: 10.1371/journal.pone.0073539
  contributor:
    fullname: Hamre
– volume: 9
  start-page: 31
  year: 2014
  ident: 10.1016/j.epidem.2016.03.003_bib0105
  article-title: Large scale modelling of salmon lice (Lepeophtheirus salmonis) infection pressure based on lice monitoring data from Norwegian salmonid farms
  publication-title: Epidemics
  doi: 10.1016/j.epidem.2014.09.007
  contributor:
    fullname: Kristoffersen
– volume: 8
  start-page: e79276
  year: 2014
  ident: 10.1016/j.epidem.2016.03.003_bib0020
  article-title: The effect of temperature on anopheles mosquito population dynamics and the potential for malaria transmission
  publication-title: PLOS ONE
  doi: 10.1371/journal.pone.0079276
  contributor:
    fullname: Beck-Johnson
– volume: 102
  start-page: 53
  year: 2012
  ident: 10.1016/j.epidem.2016.03.003_bib0095
  article-title: Effectiveness of emamectin benzoate for treatment of Lepeophtheirus salmonis on farmed Atlantic salmon Salmo salar in the Bay of Fundy, Canada
  publication-title: Dis. Aquat. Organ.
  doi: 10.3354/dao02517
  contributor:
    fullname: Jones
– volume: 72
  start-page: 1825
  year: 2008
  ident: 10.1016/j.epidem.2016.03.003_bib0045
  article-title: Effects of varying salinities on Lepeophtheirus salmonis survival on juvenile pink and chum salmon
  publication-title: J. Fish Biol.
  doi: 10.1111/j.1095-8649.2008.01839.x
  contributor:
    fullname: Connors
– volume: 36
  start-page: 25
  year: 2013
  ident: 10.1016/j.epidem.2016.03.003_bib0195
  article-title: Modelling salmon lice, Lepeophtheirus salmonis, reproduction on farmed Atlantic salmon Salmo salar L
  publication-title: J. Fish Dis.
  doi: 10.1111/j.1365-2761.2012.01415.x
  contributor:
    fullname: Stormoen
– year: 2014
  ident: 10.1016/j.epidem.2016.03.003_bib0100
  article-title: Prioritization of knowledge needs for sustainable aquaculture: a national and global perspective
  publication-title: Fish Fish.
  contributor:
    fullname: Jones
– volume: 279
  start-page: 1950
  year: 2012
  ident: 10.1016/j.epidem.2016.03.003_bib0055
  article-title: Critical thresholds in sea lice epidemics: evidence, sensitivity and subcritical estimation
  publication-title: Proc. R. Soc. B: Biol. Sci.
  doi: 10.1098/rspb.2011.2210
  contributor:
    fullname: Frazer
– volume: 71
  start-page: 201
  year: 2006
  ident: 10.1016/j.epidem.2016.03.003_bib0035
  article-title: Effect of environmental salinity on sea lice Lepeophtheirus salmonis settlement success
  publication-title: Dis. Aquat. Organ.
  doi: 10.3354/dao071201
  contributor:
    fullname: Bricknell
– volume: 306
  start-page: 191
  year: 2010
  ident: 10.1016/j.epidem.2016.03.003_bib0160
  article-title: Assessing topical treatment interventions on Scottish salmon farms using a sea lice (Lepeophtheirus salmonis) population model
  publication-title: Aquaculture
  doi: 10.1016/j.aquaculture.2010.05.006
  contributor:
    fullname: Robbins
– volume: 28
  start-page: 603
  year: 2005
  ident: 10.1016/j.epidem.2016.03.003_bib0150
  article-title: A mathematical model of the growth of sea lice, Lepeophtheirus salmonis, populations on farmed Atlantic salmon, Salmo salar L., in Scotland and its use in the assessment of treatment strategies
  publication-title: J. Fish Dis.
  doi: 10.1111/j.1365-2761.2005.00665.x
  contributor:
    fullname: Revie
– start-page: 1
  year: 2015
  ident: 10.1016/j.epidem.2016.03.003_bib0210
  article-title: Basic reproduction ratios for periodic compartment models with time delay
  publication-title: J. Dyn. Differ. Equ.
  contributor:
    fullname: Zhao
– start-page: 153
  year: 1993
  ident: 10.1016/j.epidem.2016.03.003_bib0155
  article-title: The reproductive output of Lepeophtheirus salmonis adult females in relation to seasonal variability of temperature and photoperiod
  contributor:
    fullname: Ritchie
– volume: 62
  start-page: 229
  year: 1994
  ident: 10.1016/j.epidem.2016.03.003_bib0025
  article-title: Sensitivity and uncertainty analysis of complex models of disease transmission: an HIV model, as an example
  publication-title: Int. Stat. Rev. [Revue Internationale de Statistique]
  doi: 10.2307/1403510
  contributor:
    fullname: Blower
– volume: 2
  start-page: 281
  year: 2005
  ident: 10.1016/j.epidem.2016.03.003_bib0075
  article-title: Perspectives on the basic reproductive ratio
  publication-title: J. R. Soc. Interface
  doi: 10.1098/rsif.2005.0042
  contributor:
    fullname: Heffernan
– volume: 36
  start-page: 515
  year: 2013
  ident: 10.1016/j.epidem.2016.03.003_bib0170
  article-title: Use of Atlantic salmon, Salmo salar L., farm treatment data and bioassays to assess for resistance of sea lice, Lepeophtheirus salmonis, to emamectin benzoate (SLICE® ) in British Columbia, Canada
  publication-title: J. Fish Dis.
  doi: 10.1111/jfd.12018
  contributor:
    fullname: Saksida
– volume: 320
  start-page: 164
  year: 2011
  ident: 10.1016/j.epidem.2016.03.003_bib0060
  article-title: Use of a mathematical model to describe the epidemiology of Lepeophtheirus salmonis on farmed Atlantic salmon Salmo salar in the Hardangerfjord, Norway
  publication-title: Aquaculture
  doi: 10.1016/j.aquaculture.2011.03.017
  contributor:
    fullname: Gettinby
– volume: 31
  start-page: 947
  year: 2008
  ident: 10.1016/j.epidem.2016.03.003_bib0115
  article-title: Factors associated with changing efficacy of emamectin benzoate against infestations of Lepeophtheirus salmonis on Scottish salmon farms
  publication-title: J. Fish Dis.
  doi: 10.1111/j.1365-2761.2008.00969.x
  contributor:
    fullname: Lees
– volume: 10
  start-page: e0139128
  year: 2015
  ident: 10.1016/j.epidem.2016.03.003_bib0130
  article-title: Using agent-based modelling to predict the role of wild refugia in the evolution of resistance of sea lice to chemotherapeutants
  publication-title: PLoS ONE
  doi: 10.1371/journal.pone.0139128
  contributor:
    fullname: McEwan
– volume: 290
  start-page: 263
  year: 2005
  ident: 10.1016/j.epidem.2016.03.003_bib0190
  article-title: Population dynamics of salmon lice Lepeophtheirus salmonis on Atlantic salmon and sea trout
  publication-title: Mar. Ecol. Prog. Ser.
  doi: 10.3354/meps290263
  contributor:
    fullname: Stien
– volume: 33
  start-page: 913
  year: 2010
  ident: 10.1016/j.epidem.2016.03.003_bib0165
  article-title: The efficacy of emamectin benzoate against infestations of sea lice, Lepeophtheirus salmonis, on farmed Atlantic salmon Salmo salar L., in British Columbia
  publication-title: J. Fish Dis.
  doi: 10.1111/j.1365-2761.2010.01192.x
  contributor:
    fullname: Saksida
– volume: 45
  start-page: 559
  year: 2015
  ident: 10.1016/j.epidem.2016.03.003_bib0175
  article-title: Gone with the flow: current velocities mediate parasitic infestation of an aquatic host
  publication-title: Int. J. Parasitol.
  doi: 10.1016/j.ijpara.2015.03.006
  contributor:
    fullname: Samsing
– volume: 10
  start-page: 741
  year: 2008
  ident: 10.1016/j.epidem.2016.03.003_bib0205
  article-title: EST and mitochondrial DNA sequences support a distinct pacific form of salmon louse, Lepeophtheirus salmonis
  publication-title: Mar. Biotechnol.
  doi: 10.1007/s10126-008-9112-y
  contributor:
    fullname: Yazawa
– volume: 32
  start-page: 115
  year: 2009
  ident: 10.1016/j.epidem.2016.03.003_bib0050
  article-title: The global economic cost of sea lice to the salmonid farming industry
  publication-title: J. Fish Dis.
  doi: 10.1111/j.1365-2761.2008.01011.x
  contributor:
    fullname: Costello
– volume: 279
  start-page: 2330
  year: 2012
  ident: 10.1016/j.epidem.2016.03.003_bib0085
  article-title: Sea lice as a density-dependent constraint to salmonid farming
  publication-title: Proc. R. Soc. B: Biol. Sci.
  doi: 10.1098/rspb.2012.0084
  contributor:
    fullname: Jansen
– volume: 24
  start-page: 176
  year: 2008
  ident: 10.1016/j.epidem.2016.03.003_bib0200
  article-title: Physiology and immunology of Lepeophtheirus salmonis infections of salmonids
  publication-title: Trends Parasitol.
  doi: 10.1016/j.pt.2007.12.010
  contributor:
    fullname: Wagner
– volume: 8
  start-page: e64039
  year: 2013
  ident: 10.1016/j.epidem.2016.03.003_bib0005
  article-title: Space-time modelling of the spread of salmon lice between and within Norwegian marine salmon farms
  publication-title: PLoS ONE
  doi: 10.1371/journal.pone.0064039
  contributor:
    fullname: Aldrin
– volume: 21
  start-page: 109
  year: 2001
  ident: 10.1016/j.epidem.2016.03.003_bib0180
  article-title: An improved method for experimental infection of salmon (Salmo salar L.) with salmon lice, Lepeophtheirus salmonis (Kroyer)
  publication-title: Bull. Eur. Assoc. Fish Patholog.
  contributor:
    fullname: Sevatdal
– volume: 9
  start-page: 467
  year: 2006
  ident: 10.1016/j.epidem.2016.03.003_bib0010
  article-title: Seasonality and the dynamics of infectious diseases: seasonality and infectious diseases
  publication-title: Ecol. Lett.
  doi: 10.1111/j.1461-0248.2005.00879.x
  contributor:
    fullname: Altizer
– volume: 14
  start-page: 13
  year: 2006
  ident: 10.1016/j.epidem.2016.03.003_bib0040
  publication-title: Rev. Fish. Sci.
  doi: 10.1080/10641260500448893
  contributor:
    fullname: Brooks
– volume: 23
  start-page: 114
  year: 1983
  ident: 10.1016/j.epidem.2016.03.003_bib0140
  article-title: The systematic formulation of population models for insects with dynamically varying instar duration
  publication-title: Theor. Popul. Biol.
  doi: 10.1016/0040-5809(83)90008-4
  contributor:
    fullname: Nisbet
– volume: 71
  start-page: 425
  year: 1991
  ident: 10.1016/j.epidem.2016.03.003_bib0090
  article-title: Development, growth, and survival of Lepeophtheirus salmonis (Copepoda: Caligidae) under laboratory conditions
  publication-title: J. Mar. Biol. Assoc. U. K.
  doi: 10.1017/S0025315400051687
  contributor:
    fullname: Johnson
– volume: 107
  start-page: 22599
  year: 2010
  ident: 10.1016/j.epidem.2016.03.003_bib0125
  article-title: Relationship of farm salmon, sea lice, and wild salmon populations
  publication-title: Proc. Natl. Acad. Sci. U. S. A.
  doi: 10.1073/pnas.1009573108
  contributor:
    fullname: Marty
– volume: 9
  start-page: e88465
  year: 2014
  ident: 10.1016/j.epidem.2016.03.003_bib0065
  article-title: Modelling the impact of temperature-induced life history plasticity and mate limitation on the epidemic potential of a marine ectoparasite
  publication-title: PLOS ONE
  doi: 10.1371/journal.pone.0088465
  contributor:
    fullname: Groner
– volume: 4
  start-page: 113
  year: 2000
  ident: 10.1016/j.epidem.2016.03.003_bib0135
  article-title: Lifespan and reproductive capacity of sea lice, (Lepeophtheirus salmonis), under laboratory conditions
  publication-title: Aquac. Assoc. Can.
  contributor:
    fullname: Mustafa
– volume: 271
  start-page: 159
  year: 2010
  ident: 10.1016/j.epidem.2016.03.003_bib0145
  article-title: Disrupting seasonality to control diseases outbreaks: the case of koi herpes virus
  publication-title: J. Theor. Biol.
  doi: 10.1016/j.jtbi.2010.12.004
  contributor:
    fullname: Omori
– year: 2011
  ident: 10.1016/j.epidem.2016.03.003_bib0015
  contributor:
    fullname: Beamish
– volume: 31
  start-page: 805
  year: 2000
  ident: 10.1016/j.epidem.2016.03.003_bib0080
  article-title: Egg production in the salmon louse [Lepeophtheirus salmonis (Kroyer)] in relation to origin and water temperature
  publication-title: Aquac. Res.
  doi: 10.1046/j.1365-2109.2000.00512.x
  contributor:
    fullname: Heuch
– volume: 179
  start-page: 401
  year: 2012
  ident: 10.1016/j.epidem.2016.03.003_bib0110
  article-title: Allee effects may slow the spread of parasites in a coastal marine ecosystem
  publication-title: Am. Nat.
  doi: 10.1086/664458
  contributor:
    fullname: Krkošek
– volume: 254
  start-page: 178
  year: 2008
  ident: 10.1016/j.epidem.2016.03.003_bib0120
  article-title: A methodology for performing global uncertainty and sensitivity analysis in systems biology
  publication-title: J. Theor. Biol.
  doi: 10.1016/j.jtbi.2008.04.011
  contributor:
    fullname: Marino
– volume: 15
  start-page: 32
  year: 2014
  ident: 10.1016/j.epidem.2016.03.003_bib0185
  article-title: Pacific and Atlantic Lepeophtheirus salmonis are allopatric subspecies: Lepeophtheirus salmonis and L. salmonis oncorhynchi subspecies novo
  publication-title: BMC Genetics
  doi: 10.1186/1471-2156-15-32
  contributor:
    fullname: Skern-Mauritzen
SSID ssj0064113
Score 2.2671342
Snippet Highlights • We incorporate temperature and salinity into a model of sea lice development. • We show different annual reproductive peaks between British...
•We incorporate temperature and salinity into a model of sea lice development.•We show different annual reproductive peaks between British Columbia and...
Sea lice (Lepeophtheirus salmonis) are a significant source of monetary losses on salmon farms. Sea lice exhibit temperature-dependent development rates and...
SourceID doaj
proquest
crossref
pubmed
elsevier
SourceType Open Website
Aggregation Database
Index Database
Publisher
StartPage 8
SubjectTerms Animals
Aquaculture
British Columbia
Copepoda
Delay differential equations
Female
Fish Diseases - epidemiology
Infectious Disease
Internal Medicine
Mathematical model
Population Dynamics
Salmon
Sea lice
Seasonality
Seasons
Title A Model For Sea Lice ( Lepeophtheirus salmonis ) Dynamics In A Seasonally Changing Environment
URI https://www.clinicalkey.es/playcontent/1-s2.0-S1755436516300111
https://dx.doi.org/10.1016/j.epidem.2016.03.003
https://www.ncbi.nlm.nih.gov/pubmed/27663786
https://search.proquest.com/docview/1823036556
https://doaj.org/article/2f82ffbaad9f4783aa8011931f699b80
Volume 16
hasFullText 1
inHoldings 1
isFullTextHit
isPrint
link http://sdu.summon.serialssolutions.com/2.0.0/link/0/eLvHCXMwrV3NT90wDI8Gp0nTxD5gb7ApkziMQ7UmafNxZBuIw7QLQ9phUpQ2jngIFUR5h_332En7BAfEhWvbtI7t2E5j_8zYvumTautAPcJUqhpIqrJguypqFzsQEF1Oojk5Nb__2p9HBJOzbvVFOWEFHrgw7ptMVqbUhRBdaoxVIViCKVMiaec6W3brtZk3U8UG60bkxsjoG9uqUbqdi-ZyZhfk3quU1qULwKl64JQydv8D3_RY7Jl90PEWez0Fj_ywEP2GvYDhLXtV_rzxUlD0jv075Lm9DcdwlKMic7wJ_OsvoGTx83wwsBr5GC5RAZfjAY-lJ_3IlwMPNCAH55f_ea4JRs_G7xXDvWdnx0d_fpxUUw-Fqm-lu63ahELCGUrcdTZNANMl0QeFqzCkoCS0najBai1j6F2ThLZ1alPUIKPq6Ihtm20OVwN8YNwFFGwwTkR8E_p1l_om9hGNBMZE0cKCVTMT_XWByvBzDtmFL0z3xHRfK4IkXbDvxOn1swR0nS-g-P0kfv-U-BfMzHLycy0pWj8Yp6U4euFH6Wt_SrpAqiAIZAwt_P2RU7RRoggkYvkE4V9mhfC4GOmEJQxwtcJv0bElfqPVC7ZTNGU9PWkwuDNWf3yOae-yl0RQSXbbY5u3Nyv4xDbGuPqcF8Id_aIK_w
link.rule.ids 315,782,786,866,2107,27934,27935
linkProvider Directory of Open Access Journals
openUrl ctx_ver=Z39.88-2004&ctx_enc=info%3Aofi%2Fenc%3AUTF-8&rfr_id=info%3Asid%2Fsummon.serialssolutions.com&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.atitle=A+model+for+sea+lice+%28Lepeophtheirus+salmonis%29+dynamics+in+a+seasonally+changing+environment&rft.jtitle=Epidemics&rft.au=Rittenhouse%2C+Matthew+A.&rft.au=Revie%2C+Crawford+W.&rft.au=Hurford%2C+Amy&rft.date=2016-09-01&rft.pub=Elsevier+B.V&rft.issn=1755-4365&rft.eissn=1878-0067&rft.volume=16&rft.spage=8&rft.epage=16&rft_id=info:doi/10.1016%2Fj.epidem.2016.03.003&rft.externalDocID=S1755436516300111
thumbnail_l http://covers-cdn.summon.serialssolutions.com/index.aspx?isbn=/lc.gif&issn=1755-4365&client=summon
thumbnail_m http://covers-cdn.summon.serialssolutions.com/index.aspx?isbn=/mc.gif&issn=1755-4365&client=summon
thumbnail_s http://covers-cdn.summon.serialssolutions.com/index.aspx?isbn=/sc.gif&issn=1755-4365&client=summon