Natbib does not show author year but author numeric

\documentclass{elsarticle}
\usepackage{natbib}

\begin{document}
Artificial reefs (\citet{seaman2013artificial}).

\bibliographystyle{plainnat} %
\bibliography{ref_ar1}

\end{document}


where my ref_ar1 contains

@book{seaman2013artificial,
title={Artificial habitats for marine and freshwater fisheries},
author={Seaman Jr, William},
year={2013},
}


This gives me result as follows, but I want to have author year, i.e., Seaman Jr (2013) instead of numerics. Could someone give me a hand? Many thanks in advance.

Artificial reefs (Seaman Jr [1]). [1] William Seaman Jr. Artificial habitats for marine and freshwater fisheries. Academic Press, 2013.

\documentclass{elsarticle}
\usepackage{natbib}
\bibliographystyle{abbrvnat}
\setcitestyle{authoryear,open={(},close={)}}

\begin{document}

Artificial reefs (\citet{seaman2013artificial}).

\bibliography{refs}
\end{document}


It gives this result:

Note: \bibliography{refs} was used because I named my .bib file "refs.bib" -- which contained only the reference you provided

• @Sissi - In response to your comment about {elsarticle} I'm not exactly sure what else you need help with. The code I provided in my answer gives the result that I provided an image of. If you give me more information, perhaps I can help you further. If this is no longer an issue or if I've given you as much help as you've needed, I'd ask that you please press the check mark next to my answer to accept it. That will give me credit for having provided you with the best answer, and I'd greatly appreciate it. – J.D. Oct 4 '16 at 3:47