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ALIMENTACION DE REINETA, TASA DE CONSUMO Y CONSUMO/BIOMASA

KLARIAN SA, MOLINA BE, CANALES-CERRO C & HERNANDEZ MF.

FIPA: 2015-20

ARANCIBIA ET AL. (2015)

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Brama australis

2

BRAMIDAE

6 Generos y 18 spp

Brama

Ton

0 1500 3000 4500 6000

ENE FEB MAR ABR MAY JUN JUL AGO SEP OCT NOV DIC

3,309

5,072 5,289

2,582

1,239 1,800 1,362

2,433 2,736 2,654 2,466 3,276

DESEMBARQUES 2015

INTRODUCCIÓN

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TROFODINAMICA 3

MODELOS TRÓFICOS

Función Esctructura

dinámica predador-presa

MODELOS EBE

Multispecies virtual population analysis is an extension of single-species virtual population analysis (SSVPA) and esti- mates fishing mortality, recruitment, stock abundance, and predation mortality based on catch-at-age data and stomach content data. Therefore, MSVPA uses the same equations and backward algorithm as SSVPA (Gulland 1965). Abundance for the plus group and the final year of the assessment is calculated from Baranov’s catch equation,

Na;tþ ¼ Ca;tZa;t

Fterm;a;tð1 # e#Za;tÞ ; (1)

where Ca,t represents the annual catch at age; Za,t represents the total mortality at age (Za,t = Fterm,a,t + Ma,t); Fterm,a,t represents the terminal fishing mortality at age; Ma,t represents natural mortality (described in detail below); and Na;tþ represents the abundance of the plus group or the abundance of age-class a in the final year of the assessment (2007). The abundance of the remaining age-classes is backward calculated as

Na#1;t#1 ¼ Na;teZa;t: (2)

Equation (2) is also used directly to estimate recruitment (N0,t).

Fishing mortality at age is also calculated iteratively from equation (1).

The MSVPA differs from SSVPA primarily by separating natural mortality (M) into two components: residual mortality (M1) and predation mortality (M2). Residual mortality encom- passes several causes of mortality, such as aging, starvation, diseases, and predation by other species not included in the model; M1 is assumed to be constant for each age-class within each species. This separation hypothesis allows predation mor- tality to be estimated for each age-class through time. Predation mortality is calculated with the following equation (Sparre 1991),

M2;p;a ¼ X

i

X

j

N! i;jRi;jSp;a;i;j Bof Si;of þ P

p

P

a

N! p;aW! p;aSp;a;i;j ; (3)

where M2,p,a is the predation mortality of prey p at age a; !Ni;j is the average abundance of predator i at age j !!Ni;j ¼ Ni;j;tþ1Zi;j;t#Ni;j;t"

; Rij is the annual ration (total annual food consumption, kg) for the predator species; Sp,a,i,j is the suitability coefficient for each predator–prey combination; Bof is the biomass of other prey (“other food”) available to the predator; Si,of is the suitability coefficient for the predator–other prey combination; !Np;a is the average abundance of prey p at age a; and !Wp;a is the average weight of the prey. For simplicity, the index t for time has been omitted from equation (3).

Suitability coefficients reflect the predator’s diet composi- tion relative to the available food (Sparre 1991). Estimation of suitability is based on stomach content data according to the following operational definition:

Sp;a;i;j ¼ Up;a;i;j= !Np;aWp;a P

p

P

a

Up;a;i;j= !Np;aWp;a ; (4)

where Up,a,i,j is the observed food composition in the preda- tor’s stomach contents; a is the age of prey p; and j is the age of predator i. Predator/prey suitability values have also been defined as a weighting factor determining the availability of prey p as food for predator i (Gislason and Sparre 1987).

Solution of the previous equations (1–4) requires the use of three nested iterative algorithms (Sparre 1991). More details on MSVPA assumptions, equations, and algorithms are provided by Sparre (1991) and Magnusson (1995).

Due to its complexity, MSVPA requires several types of input data, including stomach content data, annual predator ration, M1, catch at age, and Fterm, all of which are described below.

The food composition or stomach content data are probably the most important data for estimating predation mortality M2 in the MSVPA. However, diet composition information is scarce for SCDF species; therefore, we considered a different approach for these fisheries based on the work of Ursin (1973). The approach uses parameters from the predator–prey size ratios to arrive at a theoretical estimate of Ursin’s prey selectivity index.

Using a simplification from Bogstad et al. (2003), the suit- ability coefficients were calculated with the following equation:

Sp;a;i;j ¼ e #

ln Wi;j=Wp;að Þ

ð Þ2

2σ2

# $

; (5)

where Wi,j is the weight of predator i at age j; and Wp,a is the weight of prey p at age a. The constant η represents the mean log ratio between the predator weight and prey weight,

FIGURE 1. Predation interactions for the species system used in the multispecies virtual population analysis model defined for the southern Chilean demersal fishery.

352 JURADO-MOLINA ET AL.

Jurado-Molina et al. 2016

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METODOS EN TROFODINAMICA 4

SCA

ACDR

HM

SIA FECAS

SCA

Provee info. presas Incertidumbre cero

SIA

Info a largo plazo

Inferencias de consumo

‣ Sesgos debido a las TDg

‣ Info a corto plazo

‣ Alta incertidumbre - sin SCA

‣ Elevate costo para continua eva.

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ENTENDIENDO SIA EN ECOLOGÍA TRÓFICA

TIEMPO δ

δ

PLASMA SANGRE

HIGADO

MUSCULO

HUESO

DIAS SEMANAS MESES

HISTORIA DE VIDA

Kohn 1999

PRESA CONSUMIDA POR EL PREDATOR + PRESA ES ASIMILADA POR EL PREDADOR.

=

EL VALOR DE SIA DE PREDADOR, REFLEJA LA “SEÑAL”

ISOTOPICA DE LA PRESA

5

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ENTENDIENDO SIA EN ECOLOGÍA TRÓFICA

δ13C(‰) δ15

N(‰)

HABITAT - ZONA DE ALIMENTACIÓN OCEANICO

PELAGICO

NERITICO BENTONICO NIGEL TRÓFICO

CARBONO:

COMO ES GASTADA ESA ENEREGIA NITROGENO:

CUANTA ENERGÍA ENTREGA LAS PRESA

6

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ALIMENTACIÓN DE BRAMA AUSTRALIS

▸ Siguiendo los TTR FIPA 2015:20…

▸ 1. Describir la dieta de Reinetas durante 2016, a través de SCA - SIA

▸ 2. Calcular el consumo de ailmento for metodos SCA y SIA

▸ 3. Calcular Cosumo/Biomasa

Muñoz et al (1995)

PACIFÍCO

0 25 50 75 100

1995 2002 2014

EUF

MESOP CEF

SARD

Garcia & Chong (2002) Santa Cruz et al (2014)

Horn et al (2013)

N. ZELANDA

5 4

91

MESOP

CAM ZOO

7

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MATERIALES Y METODOS 8

1448 SCA

457

SIA 457 REINETAS

+

213 PRESAS CALORIMETRIA

CONGELADAS -20º SCA; 80º SIA Y CALORIMETRÍA - UNAB -

MUESTRAS ZONA

TALCAHUANO LEBU

PTO CHACABUCO TEMPORALIDAD

ENE-ABR

MAY-AGO TAMAÑO

<39 CM

>40 CM

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SCA 9

Lab. work - UNAB -

ESTOMAGOS

LLENO VACIO

PRESAS

P, N, F

>GD- SIA TAXON

Analisis de datos

Importancia de la presa; %P Arancibia et al. (2015)

Curva de diversidad Trófica Gelsleichther et al. (1999)

W test Zar (1999)

Consumo alimento SCA

Alimentacion frecuente Elliot & Persson (1978)

Alimentacion intermitente Diana (1979)

Q y Q/B

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SIA - CALORIMETRÍA 10

Lab. work - UNAB -

0.4-0.6 MG

LOPEZ ET AL. (2013)

~10 MG; EX. LIPIDOS (C:M 2:1)

HUSSEY ET AL (2010)

13C, 15N, %CN; STANDARD: PEE DEE BELEMITA 13C Y N ATMOSFERICO 15N

Analisis de datos

MixSIAR, MCMC Stock & Semmens et al. (2013)

A priori (SCA), α Klarian et al (unpublished)

TP, RInSP Araujo et al (2013)

Consumo alimento SIA

Balance enegertico, combinacion calorimetria - SIA Inger et al.

(2006)

ANOVA

Agrupacion de presas Fry (2013)

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RESULTADOS

PRUEBAS; DIAGNOSTICOS Y LIPIDOS

11

LIPIDOS

δ13C‰

-18 -16.75 -15.5 -14.25 -13

C:N

2 3 4 5

δ15N‰

0 6 12 18 24

LH

0 20 40 60

y = 0.1721x + 9.5723 R² = 0.2016

δ13C‰

-18 -16.75 -15.5 -14.25 -13

LH

0 20 40 60

y = 0.041x - 17.64 R² = 0.0951

SCA INFO

100% MATCH

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RESULTADOS SCA 12

PP. SCA

50.2% 49.8%

Vacios

Llenos

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RESULTADOS SCA -GENERAL-

DIETA GENERAL

Ítem P %P

Cefalopoda

Dosidicus gigas 13.47 0.33

Gonatus sp. 1.13 0.03

Graneledone sp. 0.22 0.01

Histioteuthis sp. 0.24 0.01

Ommastrephes bartramii 23.46 0.58

Onykia sp 4.19 0.10

Todarodes sp. 17.81 0.44

Onychoteuthidae 0.26 0.01

Oegopsida 0.33 0.01

Indeterminado 148.89 3.68

Restos 49.83 1.23

Subtotal 259.83 6.42

Crustacea

Euphausia mucronata 208.38 5.15

Euphausia sp. 568.95 14.05

Munida gregaria 34.92 0.86

Sergestes arcticus 407.86 10.07

Amphipoda 57.43 1.42

Larva Decapoda 1.05 0.03

Larva Stomatopoda 162.13 4.00

Isopoda 0.09 0.00

Restos 657.12 16.23

Subtotal 2097.93 51.80

Peces

Maurolicus parvipinnis 152.27 3.76

Sprattus fueguensis 7.18 0.18

Strangomera bentincki 471.25 11.64

Myctophidae 274.82 6.79

Restos 786.56 19.42

Subtotal 1692 42

TOTAL 4050 100

CAT. MAYORES

%P

0 5.5 11 16.5 22

CAM CEF CLUPE EUF MESO STOMA

13

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RESULTADOS SCA -TAMAÑOS- 14

CAM CEF CLUPE EUF MESO STOMA

%P

0 8 16 24 32 40

Tamaño 1

Tamaño 2

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RESULTADOS SCA -ZONA-

CAM CEF CLUPE EUF MESO STOMA

%P

0 8 16 24 32 40

Talcahuano Lebu

Chacabuco

15

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RESULTADOS SCA -TIEMPO-

CAM CEF CLUPE EUF MESO STOMA

%P

0 8 16 24 32 40

ENE-ABR MAY-AGO

16

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RESULTADOS SIA -BIPLOT TAMAÑOS- 17

δ15N‰

5 9.75 14.5 19.25 24

δ13C‰

-23 -20.25 -17.5 -14.75 -12

STOMA MESO

EUF

CLUPE CEF

CAM

Tamaño 1 Tamaño 2 CAM

CEF

CLUPE EUF

MESO STOMA

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RESULTADOS SIA -BIPLOT ZONAS- 18

δ15N‰

5 9.75 14.5 19.25 24

δ13C‰

-18 -16.5 -15 -13.5 -12

CHBC LEBU

THNO

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RESULTADOS SIA -BIPLOT TIEMPO- 19

δ15N‰

5 9.75 14.5 19.25 24

δ13C‰

-18 -16.5 -15 -13.5 -12

ENE-ABR

MAY-AGO

RESUMEN

δ13C δ15N NT

General -15.89 ± 0.80 16.94 ± 2.33 3.9

Período Enero-Abril -15.93 ± 0.56 16.91 ± 2.30 3.9 Mayo-Agosto -15.83 ± 0.89 16.98 ± 2.37 4.0 Tamaño ≤39 cm -16.06 ± 1.03 15.88 ± 1.73 3.6

≥40 cm -15.76 ± 0.55 17.71 ± 2.40 4.2 Localidad

de

desembarque

Talcahuano -15.75 ± 0.58 17.57 ± 2.79 4.1 Lebu -15.59 ± 0.43 18.69 ± 1.48 4.5 PuertoChacabuco .-15.96 ± 1.00 15.86 ± 1.70 3.6

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RESULTADOS SIA % DIETARIA 20

% contribution

0 25 50 75 100

GENERAL ENE-ABRIL MAY-AGO TM1 TM2 THN LEBU CHBC

18.7 36.8

47.2 61.9 55.7

42.1 56.3 69.8

CAM CEF CLUPE EUF MESO STOMA

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RESULTADOS CONSUMO SCA

CONSUMO

Total CAM CEF CLUPE EUF MESO STOMA

TEG (gr/hora) 0.30 0.26 0.38 0.27 0.22 0.23 0.37

Wprom contenido (gr)

2.91 12.75 0.53 52.40 6.80 4.06 0.16

Tasa incorporación

(gr/hora) 172.02 157.72 363.93 360.88 39.20 39.99 154.14

RD1 E&P (gr día) 2094.33 1920.29 4430.80 4393.69 477.26 486.90 1876.68

RD2 D. (gr día) 21.08 80.76 4.81 338.93 35.23 22.21 1.40

RD1/W 10.43 1.31 3.02 2.99 0.32 0.33 1.28

RD2/W 1 0.05 0.00 0.23 0.02 0.02 0.00

Q - Q/B

30 dias 120 dias

Biomasa (toneladas) 2.12

Q (toneladas) 3.50 13.99

Q/B (adimensional) 1.65 6.60

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RESULTADOS CONSUMO SIA - CALORIMETRIA

‣ 4.41 ± 0.86 calories gr Kg. 100 gr 441 peso corporal

‣ Cdr= 0.62 gr inmaduros y 0.49 gr maduros; 2.73 cal, 2.16 cal para general biomass

‣ Consumo 11.98 gr dia; TGE 0.5 gr h, lo qui equivalio 0.82% peso corporal

22

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DISCUSION

Número de estomagos due suficiente para estudiar la dieta de la reinetas SCA - SIA concuerdan con los reportes previous

Existen diferencias ontogeneticas

δ13C y δ15N difieren con respect a otras especies de Reinetas, presentando un TP superior El consume de reineta se ajusta a las de un predator de alimentacion frequente

Diferencias entre los metodos.

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CONCLUSIONES

‣ La reineta presenta una alimentación basada en eufausidos, peces y cefalópodos. Con clara preferencia de eufausidos.

‣ Los individuos presentaron diferenciación en relación al tamaño corporal. Peces de menor tamaño se alimentan de eufausidos en comparación con aquellos de mayor tamaño que se alimentan de pequeños pelágicos. Sin embargo, estas diferencias pueden estar asociadas a cambios espaciales de las reinetas.

‣ Los valores de estabilidad isotópica posicionan a la reineta como una especie pelágica y que se alimenta en zonas costeras.

‣ La reineta presenta un patrón de consumo del tipo frecuente, con una tasa de evacuación

gástrica de 0,3 g/hora, lo cual hace que estos consuman el 1% de su peso corporal.

Referencias

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